Shiur 09: The Sabbath in the Book of Yirmeyahu (17:19-27)

  • Rav David Sabato

This week’s shiurim are dedicated in commemoration of the yarhzeit of 
Rabbi Lipman Z. Rabinowitz, by his family

Please daven for a refua sheleima for YHE alumnus 
Rav Daniel ben Miriam Chaya Rut


The prophecy in chapter 17 continues the series of prophecies dealing with the historical covenant between God and Israel in chapters 7, 26, and 11. In chapters 18-19, we find two more prophecies that complete this series of prophecies that may be called "the prophecies about the covenant." We will deal with those prophecies in the coming shiurim. After concluding our study of this series of prophecies, we will return to the chapters that we skipped and examine the personal dimension of Yirmeyahu as a prophet as is revealed in these chapters.

The prophecy in chapter 17 is exceptional among the prophecies of Yirmeyahu and the prophecies of rebuke in general in that it focuses exclusively upon one mitzva, the commandment to keep the Sabbath, upon which the future existence of Jerusalem is conditional. This, of course, raises a question regarding the uniqueness of the commandment of the Sabbath and its relation to the destruction of Jerusalem and the Temple.

The prophecy is divided into two parts, following a verse of introduction [19], which contains the instruction to deliver the prophecy and the location where it is to be delivered – at “the gate of the children of the people.” The first part of the prophecy [20-23] deals with the commandment and the warning about keeping the Sabbath, and the second part [24-27] is structured as a condition and its outcome, conditioning the future of Jerusalem upon the observance of the Sabbath.

The Prophecy's Opening

Thus said the Lord to me:

Go and stand in the gate of the children of the people, by which the kings of Yehuda come in and by which they go out, and in all the gates of Jerusalem.

Already at the beginning of the prophecy, we see the great similarity between it and the prophecy about the Temple of the Lord in chapter 7. Both prophecies open with a command to the prophet to stand in the gate through which the people of Yehuda come in. The gate is the most public meeting place in the city, where large numbers of people congregate, and which therefore constitutes a sound box that amplifies the effectiveness of the prophecy. Moreover, there is also a striking structural similarity between the two prophecies; both are structured as a condition and its outcome.

However, it is precisely the similarity between the prophecies that gives rise to a great difficulty in the prophecy before us. At the heart of the Yirmeyahu's prophecy about the Temple of the Lord in chapter 7 stands a series of commandments that the people had transgressed. As we saw there, this series includes the central commandments of the Ten Commandments, which are mentioned also by other prophets from different periods as the cause of the destruction and the calamity: theft, murder, adultery, lying, idol worship, and more. This is the essence of the covenant that the people violated, which includes the three most serious offenses: idolatry, forbidden sexual relations, and bloodshed. These commandments are mentioned in several places in the Torah as those whose observance or violation determines Israel's fate in their land, and the violation of which causes the land to spew out the people. This highlights the surprising fact that the prophecy of rebuke in our chapter focuses on just one commandment, the commandment regarding the Sabbath. Despite the great importance that the Torah attaches to the Sabbath, nowhere does it state that observance of the Sabbath is a condition for the people's continued existence in their country. As stated, even Yirmeyahu himself, when he alludes to the Ten Commandments in chapter 7, does not refer to the commandment of the Sabbath.

The great novelty in the prophecy stands out also in the structural and stylistic similarities between it and the "Ve-haya im shamo'a" passage in Devarim 11: "And it shall come to pass if you diligently hearken to Me… But if you will not hearken to Me." There too we find a condition and an outcome relating to the people's continued existence in their land. But there the condition relates to all the commandments and to the fulfillment of the conditions set down by the covenant entered into at Sinai: "And it shall come to pass, if you hearken diligently to My commandments which I command you this day." This sharpens the novelty of our prophecy, in which the prophet cites the conditional framework of the book of Devarim, but instead of relating to the commandments as a whole, he focuses exclusively on the commandment regarding the Sabbath.

What, then, is the deeper significance of the commandment of the Sabbath in our prophecy?

The Sabbath In Yirmeyahu's Prophecy

First, let us examine the wording of the commandment regarding the Sabbath in our prophecy [21-24]. This is a command that reiterates the ancient command to the people: "As I commanded your fathers" [22]. An examination of the wording of the command reveals that it clearly parallels the commandment regarding the Sabbath in the Ten Commandments as it appears in the book of Devarim,[1] as is evident from the following table:

Yirmeyahu 17

Devarim 5

(21) Take heed (hishamru) to yourselves

and bear no burden of the Sabbath day, nor bring it in by the gates of Jerusalem,

(22) neither carry forth a burden out of your houses on the Sabbath day,

neither do any work,

but hallow the Sabbath day,

as I commanded your fathers.

(12) Keep (shamor) the Sabbath day to sanctify it,

as the Lord your God has commanded you.

(13) Six days you shall labor, and do all your work:

(14) but the seventh day is the Sabbath of the Lord your God: on it you shall not do any work…

Therefore, the Lord your God commanded you to keep the Sabbath day.


The command opens with words "Take heed" (hishamru), which parallels the command "Keep" (shamor) in the commandment concerning the Sabbath in Devarim, Here, however, we find the addition of the words "to yourselves" (literally, "to your souls," be-nafshoteikhem), which emphasizes the danger to the soul posed by lack of observance. There is also an interesting difference regarding the scope of the prohibition. In the book of Devarim, it is only the performance of forbidden labor that is prohibited, whereas here the prophet adds to the prohibition against such labor and prefaces it with a prohibition to bring in or remove burdens from the house,[2] even though this does not actually involve forbidden labor.[3] The significance of this becomes evident in the second part of the prophecy:

(24) And it shall come to pass, if you diligently hearken to Me, says the Lord, to bring in (havi) no burden through the gates of this city on the Sabbath day, but hallow the Sabbath day, to do no work on it;

(25) then shall there enter (u-va'u) into the gates of this city kings and princes who sit upon the throne of David, riding in chariots and on horses, they, and their princes, the men of Yehuda, and the inhabitants of Jerusalem: and this city shall remain forever.

(26) And they shall come (u-va'u) from the cities of Yehuda, and from the places about Jerusalem, and from the land of Binyamin, and from the coastal plain, and from the mountains, and from the Negev, bringing (mevi'im) burnt-offerings, and sacrifices; and meal-offerings, and incense, and bringing (u-mevi'ei) sacrifices of praise to the house of the Lord.

The most prominent root in this section dealing with the reward for Sabbath observance is the root bo, "come, enter, bring," which is repeated seven times in the prophecy (five times in this section and two more times in verses 17 and 21). It connects the action with its reward, measure for measure. It is precisely the closing of the gates on the Sabbath and refraining from bringing burdens through them that will lead to a coming of great significance – the coming of kings and princes, who represent the self-rule of the Davidic monarchy. The word “Sabbath” also repeats itself seven times in this prophecy and reflects its essence – keeping the sanctity of the seventh day by limiting the comings and goings at the city gates.[4] In the next verse, the circles widen and additional guests come to the city from near and far. Restricting the burdens on those days will lead to a multifold expansion in its wake, in the form of the sacrifices that will be brought by pilgrims coming to Jerusalem. Another prominent root in this passage is yashav, and it seems that here too the principle of measure for measure is in operation. Resting and sitting at home on the Sabbath, rather than going out and taking things out, will lead to sitting in the city in security. Her kings will sit on the throne of David, and the city will sit forever in its place [25].

Corresponding to the great reward that is promised in exchange for keeping the Sabbath in the city, the prophecy ends with a threat and the punishment that can be expected if the city profanes the sanctity of the Sabbath within its limits [27]:

But if you will not hearken to Me to hallow the Sabbath day, and not to bear a burden, and if you enter (u-vo) in at the gates of Jerusalem on the Sabbath day;

then will I kindle a fire in its gates, and it shall devour the palaces of Jerusalem, and it shall not be quenched.

Here we find the seventh instance of the root bo, but here, its meaning is negative and the opposite of that in the previous section – bringing burdens in through the gates of Jerusalem on the Sabbath will lead to a kindling of fire at the gates, an action that symbolizes the coming of the enemy, and thus the cancellation of the possibility that anything else can be brought in. Here too the element of eternity stands out. Instead of the city remaining forever, it will be punished with eternal destruction: "Then will I kindle a fire… and it shall not be quenched."[5]

The Sabbath – A National "Sign of the Covenant"

In his commentary (ad loc.), the Radak suggests an explanation for the significance of the Sabbath:

He admonished them about the Sabbath, even though they were guilty of other transgressions, and even idol worship, because the Sabbath is a great principle in the belief in the creation of the world and in the belief in signs and wonders and in the keeping of the entire Torah. Anybody who faithfully observes the Sabbath will not quickly sin with regard to the other mitzvot.

But if this is the case, every prophet should have mentioned the mitzva of the Sabbath in his rebukes! Moreover, as we have seen, the rebuke here does not focus on the prohibition of forbidden labor, which is the essence of the story of creation and of most of the Torah's passages dealing with the Sabbath, but rather on the prohibition of taking things in and out. It seems, then, that the prophecy is rooted in a different issue.

A similar attitude to the uniqueness of the Sabbath and its centrality in the covenant between God and His people already appears in the Torah (Shemot 31:13-17):

Speak also to the children of Israel, saying: Verily My Sabbaths shall you keep, for it is a sign between Me and you throughout your generations; that you may know that I am the Lord who sanctifies you… Wherefore the children of Israel shall keep the Sabbath, to observe the Sabbath throughout their generations, for a perpetual covenant. It is a sign between Me and the children of Israel forever…

Here, the Sabbath is portrayed as the sign of the covenant between Israel and God, and it symbolizes Israel's consecration to God. However, the violation of the covenant is mentioned here only in individual terms:

You shall keep the Sabbath therefore; for it is holy to you: everyone that profanes it shall surely be put to death; for whoever does any work on it, that soul shall be cut off from among his people.

A similar attitude, which is based on the verses in Shemot and expands upon them, appears in the prophecy of Yechezkel, Yirmeyahu's younger contemporary (Yechezkel 20:12-13):

Moreover, also I gave them My Sabbaths, to be a sign between Me and them, that they might know that I am the Lord who sanctifies them. But the house of Israel rebelled against Me in the wilderness; they did not follow My statutes and they rejected My judgments, which if a man do, he may live by them, and My Sabbaths they greatly profaned. Then I said I would pour out My fury upon them in the wilderness, to consume them.

            Yechezkel cites here a tradition that we do not know from any other source – that the desecration of the Sabbath was grounds for destroying Israel in the wilderness! The connection to the verses in Shemot is clear – a breach of the covenant on Israel's part is punished by a breach of the covenant by God.

Only one other mitzva in the Torah is designated as a sign of the covenant – the mitzva of circumcision (Bereishit 17:11): "And you shall circumcise the flesh of your foreskin; and it shall be a sign of the covenant between Me and you." The Sabbath, then, is not just another one of the 613 commandments, but rather a fundamental and central mitzva, which stands at the foundation of the covenant between God and Israel. Both the Sabbath and circumcision express the uniqueness of the people of Israel and distinguish them from the other nations. But while the covenant of circumcision is a private and personal covenant that is sealed in one's most intimate parts, the covenant of the Sabbath is a national covenant of a most public nature. All of the nations work and conduct business on the Sabbath, whereas the people of Israel rest on that day. In practice, from a national perspective, the Sabbath is one of the most prominent markers of the Jewish People, especially when they live in exile among the other nations. The focus of spatial sanctity, the Temple, was destroyed, and it was replaced by the Temple of time, the Sabbath, which can be observed in all places.[6] Therefore the profanation of the Sabbath is one of the most striking signs of assimilation and loss of Jewish identity, from ancient times and until the present.[7]

In view of this picture of the Sabbath and its place in the world of the people of Israel, the deeper meaning of Yirmeyahu's prophecy is clarified. First, it is now clear why Yirmeyahu refers specifically to the issue of carrying burdens in and out through the city gates, the public center of the city. This is the most public work performed on the Sabbath; it determines the character of the Sabbath in the public spaces of Jerusalem the Jewish identity of the city. Even the nature of the reward is understandable in light of this. We are not dealing here with a reward measure for measure in just the technical sense, but rather in a more profound and essential sense. The preservation of the Jewish character of Jerusalem by resting on the Sabbath will preserve the sanctity of Jerusalem as a city and allow for its eternal existence and sovereignty. Only in this way will the Temple that stands at its center be able to survive and to attract pilgrims from all corners of the earth. Conversely, opening the gates will lead to the profanation of the city's sanctity and the loss of its Jewish identity, and thus it will lose its right to exist.

The unique message of the prophecy emerges also from the parallel between its opening verse and the opening of the prophecy in chapter 7:

The prophecy about The Sabbath [17:19-20]

The prophecy about the Temple of the Lord [7:1-2]

Thus said the Lord to me:


Go and stand in the gate of the children of the people, by which the kings of Yehuda come in and by which they go out, and in all the gates of Jerusalem;

and say to them: Hear the word of the Lord, you kings of Yehuda, and all Yehuda, and all the inhabitants of Jerusalem, that enter in by these gates.


The word that came to Yirmeyahu from the Lord, saying:

Stand in the gate of the Lord's house, and proclaim there this word




and say: Hear the word of the Lord, all Yehuda, that enter in at these gates to worship the Lord.


As stated, the similarity between the two openings is striking. But this similarity also reveals certain significant differences between the two prophecies that may clarify the intention of the prophecy:

  1. In chapter 7, the prophecy is directed at all of Yehuda, whereas the prophecy in chapter 17 is addressed also to the kings of Yehuda. The kings are mentioned here twice, and once again later in the prophecy [25].
  2. In chapter 7, mention is made only of those that "enter in at these gates," whereas in chapter 17, mention is made of the gate "by which they go in" and "by which they go out."
  3. The gate in chapter 7 is the gate of the house of the Lord, while here there is mention of the gate of the people and of all the gates of Jerusalem. As in chapter 7, here there is symbolic meaning to standing in the gate, in addition to its strategic location. In both prophecies, the gates are the subject of the prophecy. In chapter 7, we are dealing with the gate of the house of the Lord, to which Yirmeyahu's harsh prophecy of calamity relates. Here, on the other hand, we are dealing with the gates of the city of Jerusalem, through which the burdens are brought. The prophecy here deals with the entire city, and not just the Temple, and it focuses on its public character. Therefore, it speaks of the gates of the entire city and of going in and out through those gates. This is also the reason that the prophecy is addressed also to the kings of Yehuda, who rule the city and are responsible for its character and nature, and upon whom rests the obligation to fashion it in proper manner.[8] The reward and punishment also focus on the gates of the city and their governmental aspects, and it is precisely the Temple that is not mentioned here. The reward will lie in, among other things, the coming of kings and princes who sit on the throne of David. The punishment will come in the image of a fire that will kindle the gates of the city, and from there consume the palaces of Jerusalem, its princes and its kings who did not prevent the desecration of the Sabbath.

Echos of YIrmeyahu's Prophecy in the Recollections of Nechemya

Many years after Yirmeyahu's prophecy, in the days of the return to Zion, Nechemya recounts to God his determined efforts to preserve the sanctity of the Sabbath in Jerusalem (Nechemya 13:15-22):

(15) In those days, I saw in Yehuda some treading winepresses on the Sabbath, and bringing in sheaves of corn, and loading asses; as also wine, grapes, and figs, and all manner of burdens, which they brought into Jerusalem on the Sabbath day; and I forewarned them on the day on which they sold food.

(16) There dwelt men of Tzor there also, who brought fish and all manner of ware, and sold on the Sabbath to the children of Yehuda and in Jerusalem.

(17) Then I contended with the nobles of Yehuda and said to them, “What evil thing is this that you do, and profane the Sabbath day?

(18) Did not your fathers do thus, and did not our God bring all this evil upon us and upon this city? And yet you bring more wrath upon Israel by profaning the Sabbath.”

(19) And it came to pass that when the gates of Jerusalem began to be dark before the Sabbath, I commanded that the gates should be shut and charged that they should not be opened till after the Sabbath; and I set some of my servants at the gates, so that no burden should be brought in on the Sabbath day.

(21) So the merchants and sellers of all kinds of ware lodged outside Jerusalem once or twice.

(22) Then I forewarned them, and said to them, “Why do you lodge about the wall? If you do so again, I will lay hands on you.” From that time on, they came no more on the Sabbath.

An examination of the words of Nechemya reveals a close affinity to the prophecy of Yirmeyahu. Like Yirmeyahu, Nechemya strives to preserve the public standing of the Sabbath in Jerusalem's public areas, and he therefore focuses on commercial activity at the gates of Jerusalem on the Sabbath. Nechemya also relates explicitly to desecration of the Sabbath in the past, which was one of the causes of the destruction: "Did not your fathers do thus, and did not our God bring all this evil upon us and upon this city?" He thereby alludes to the prophecy of Yirmeyahu.

There is, however, one very important difference between the two historical situations. Yirmeyahu, it would seem, failed in his attempts to preserve the character of the city on the Sabbath through his rebukes, whereas Nechemya succeeded, and he mentions this before God. It stands to reason that this difference resulted from the different standings of the two leaders: Yirmeyahu acted as an independent prophet, with no connection to the political institutions and personalities in Jerusalem. This is probably the reason that he turns to the kings of Yehuda, who are in charge of the city and its gates and who are able to take steps to close them down on the Sabbath. Nechemya, on the other hand, is a political leader who wields political and institutional power. He is not satisfied with reproach, but rather contends with the nobles of Yehuda, orders them to close the doors, sets some of his servants at the gates, and even threatens the merchants. Only then: "From that time on, they came no more on the Sabbath."

Sitting and Going Out on the Sabbath of the Mann

The character of the Sabbath in Yirmeyahu's prophecy, which focuses on bringing burdens in and out of the city, is different from the character of the Sabbath in the Torah, which focuses on the prohibition of forbidden labors. There is, however, an allusion to it in the section dealing with the mann in Shemot 16. This is Israel's first command regarding the Sabbath, and in fact this is also the first command received by the people after the exodus from Egypt, on the way to Mount Sinai (apart from the commandments connected to remembering the exodus).

(27) And it came to pass that some of the people went out on the seventh day to gather, and they found none.

(28) And the Lord said to Moshe, “How long will you refuse to keep My commandments and my Torot?

(29) See, that the Lord has given you the Sabbath, therefore He gives you on the sixth day the bread of two days; remain every man in his place, let no man go out from his place on the seventh day.”

(30) So the people rested on the seventh day.

An examination of the character of the Sabbath in this passage reveals something interesting: Even though it is the first passage in the Torah dealing with the mitzva of the Sabbath, there is no mention here of the prohibition of forbidden labors. The focus of the Sabbath here lies in the prohibition to go out of the house to gather food (in this case, manna) from the field. Moreover, it seems that the passage interprets the word "Sabbath" (Shabbat) as a sort of abbreviation: "Remain every man in his place" (shevu ish tachtav). Thus, the Sabbath is not a day of rest from forbidden labors, as it is described in all the other passages in the Torah, but rather a day of sitting in the house and not going out, just as we saw in the book of Yirmeyahu.

What, then, is the character of the Sabbath fashioned here? On the Sabbath, a person is commanded not only to refrain from creating and from doing labor, but also not to leave his house. Leaving the house involves man's constant preoccupation with searching for food and sustenance, hunting and gathering – in our context, going out to gather the mann. All week long, a person is occupied with interacting with his surroundings, with commerce, and with attaining the food that he needs for the sake of his physical survival. On the Sabbath, he is commanded to sit in his house. He must prepare in advance a double amount of bread for the Sabbath, and he must sanctify the Sabbath and seclude himself with his family and in his inner world, with the covenant between him and God.

Yirmeyahu's prophecy develops this idea. Preserving the Sabbath involves preserving the inner uniqueness, the holy and special identity of Jerusalem and of the people of Israel as a collective. Closing the gates in this context bears the deep symbolic meaning of disengagement from the outside, from trade, and from the surrounding reality, and focusing on the sacred, the inside, and the sign of the covenant. Opening the gates, on the other hand, is not just a desecration of the Sabbath, but also the absolute breach of Jerusalem to the winds on the outside, the loss of its sacred identity and total assimilation. Nechemya's struggle to close the gates, in the wake of Yirmeyahu, fits in well with his strivings to maintain Jewish identity in an age marked by a clear and tangible danger of assimilation.[9]

(Translated by David Strauss)


[1] The affinity between the book of Yirmeyahu and the book of Devarim is well known, and as stated above, the entire structure of the prophecy follows the structure of the "Ve-haya im shamo'a" passage in Devarim 11.

[2] A similar focus on commerce and trade, rather than forbidden labors, is found in Yeshayahu 58:13: "If you restrain your foot because of the Sabbath, from pursuing your business on My holy day, and call the Sabbath a delight, the holy day of the Lord honorable; and shall honor it, not doing your own ways, nor pursing you own business, nor speaking of vain matters." From here the Sages derived prohibitions that are not forbidden labors, as the Rambam summarizes (Hilkhot Shabbat 24): "There are activities that are forbidden on the Sabbath despite the fact that they do not resemble the [forbidden] labors, nor will they lead to [the performance of] the [forbidden] labors. Why then are [these activities] forbidden? Because it is written (Yeshayahu 58:13): 'If you restrain your foot because of the Sabbath, from pursuing your business on My holy day…'; and it is written [ibid.]: 'And you shall honor it, not doing your own ways, nor pursuing your own busines, nor speaking of vain matters.' Therefore, it is forbidden for a person to go and tend to his [mundane] concerns on the Sabbath, or even to speak about them, e.g., to discuss with a partner which merchandise should be sold on the morrow or which should be bought, how this building should be constructed, or which merchandise should be taken to a particular place. Speaking about all matters of this like is included in the prohibition [against] '...speaking about [mundane] matters.' It is speaking that is forbidden. Thinking [about such matters] is permitted."

[3] The first mishna in tractate Shabbat opens with the laws of taking things out and bringing things in from one domain to another. Ri, cited in Tosafot (s.v. pashat) notes that the labor of carrying things is a "deficient labor" because, among other reasons, it lacks the creative element that characterizes forbidden labors. The Yerushalmi proposes two sources for this prohibition. One is from Moshe's words to the people in Shemot 36:6: "And Moshe gave commandment, and they caused it to be proclaimed throughout the camp saying: Let neither man nor woman do any more work for the offering of the sanctuary. So the people were restrained from bringing." The second is from the prophecy of Yirmeyahu: "R. Chizkiya said in the name of R. Acha: Derive them all from this verse: 'Neither carry forth a burden out of your houses on the Sabbath day, neither do any work.'"

[4] Another guide-word found in this prophecy is the word “Jerusalem,” which appears five times in the prophecy and another two times in the introduction. It focuses the message of the prophecy on keeping the sanctity of the seventh day in Jerusalem.

[5] This punishment parallels the punishments mentioned in the prophecies of "For three and for four" in Amos chapters 1-2, but there the fire is directed at the walls and the houses ("But I will kindle a fire in the wall"), whereas here it is directed at the gates ("Then will I kindle a fire in the gates"), since it is the gates which stand, as stated above, at the heart of the prophecy. Another difference is the intensification of the punishment through the addition of the words "and it shall not be quenched," which is connected, as stated above, to the element of eternity in the prophecy (the phrase "and it shall not be quenched" in connection with Jerusalem appears again in Yirmeyahu's prophecy in chapter 7). It is possible that the use of the expression "I will kindle a fire," rather than "I will send a fire," which is the more common expression in Amos's prophecies (six out of seven times "I will send a fire," as opposed to one instance of "I will kindle a fire"), is meant to create a linguistic connection to the sin: ve-hitzati ("I will kindle") – ve-lo totzi'u ("Neither carry forth"). For a similar play on words, see Bereishit 38:24-25: hotzi'uha… – mutzeit….

[6] This is apparently the reason why the emphasis on Sabbath observance appears primarily in the relatively late books in Scripture, as the Sabbath grew in importance in the Diaspora. This brought certain scholars to argue that the prophecy about the Sabbath in the book of Yirmeyahu is later than his time and was written only after the destruction. Regarding this argument, see M. Greenberg, “Parashat Ha-Shabbat Be-Yirmeyahu, Iyyunim Be-Sefer Yirmeyahu II, pp. 27-37.

[7] For other signs of assimilation in the period of Yirmeyahu, see the words of the contemporary prophet, Tzefanya (1:4-8): "And I will cut off the remnant of the Ba'al from this place, and the name of the idolatrous priests with the priests; and those who worship the host of heaven upon the housetops; and those who worship, who swear to the Lord, and who yet swear by Malkam; … And I will punish the princes, and the king's children, and all such as are clothed in foreign apparel…"

[8] See Radak, ad loc.: "He first called out at the gate through which the kings of Yehuda come in and go out, for they should have rebuked the people and kept the day of the Sabbath."

[9] It is interesting to note that immediately after the account of his actions on behalf of Sabbath observance, Nechemya speaks of his efforts to prevent assimilation.