The ninth plague which God brought upon the Egyptians was the plague of darkness, during which the Egyptians were unable to see or even move, whereas Benei Yisrael enjoyed ordinary light (10:22-23). Rashi cites a famous passage in the Midrash (Shemot Rabba 14:3) explaining that God brought this plague to give Benei Yisrael the opportunity to search through the Egyptians’ homes and take stock of their possessions. As we read later (11:2, 12:35), God commanded Benei Yisrael in preparation for the Exodus to ask their Egyptian neighbors for their belongings to take with them as they left, and Benei Yisrael complied. In anticipation of the people’s asking the Egyptians for their belongings, the Midrash writes, God brought darkness upon the Egyptians so that Benei Yisrael could freely search their homes and see all they had, in case the Egyptians would later deny having what to give to Benei Yisrael.
Chizkuni cites Rashi’s comments, and then notes the verse later in the parasha (12:36) which tells that at the time of the Exodus, when Benei Yisrael asked the Egyptians for their belongings, “…the Lord placed the people’s favor in their eyes…” The Torah there states that God saw to it that Benei Yisrael found favor in the Egyptians’ eyes, such that the Egyptians happily gave them their possessions. It seems that Chizkuni here questions the Midrash’s account which Rashi brings, describing how the Egyptians tried denying owning riches, and Benei Yisrael responding by listing the items they found during the plague of darkness. The Torah states explicitly that the Egyptians gave Benei Yisrael their possessions because they looked upon them favorably, not because of their failed attempt to dishonestly deny having possessions.
One possible answer to this question, as suggested by Rav Chaim Elazary in his Netivei Chaim, is that Rash did not mean that Benei Yisrael ultimately needed to resort to the lists they compiled during the plague of darkness. Perhaps, Rashi’s intent is that Benei Yisrael prepared for the possibility that the Egyptians would deny having riches by scouring the Egyptians’ homes during the plague, but in the end, this proved unnecessary, because the Egyptians happily gave them their belongings. (This explanation seems difficult to accept, however, in light of the fact that Rashi speaks of Benei Yisrael searching through the Egyptians’ homes to answer the question, “Why did He [God] bring upon them [the Egyptians] darkness.” According to the Midrash, God brought the plague of darkness for this purpose – to allow Benei Yisrael the opportunity to see what the Egyptians had in their homes, indicating that this was necessary in order for Benei Yisrael to obtain the Egyptians’ riches at the time of the Exodus.)
Alternatively, Rav Elazary writes, Rashi may have understood that although the Egyptians graciously parted with some possessions at the time of the Exodus, they tried keeping for themselves possessions with the false claim of not having more to give. Indeed, as the Torah tells, Benei Yisrael found favor in the Egyptians’ eyes and the Egyptians happily gave them some of their belongings. However, they then claimed to have given all they had, and so Benei Yisrael named their remaining possessions which they had seen during the plague of darkness.
Even if we are gracious and generous, we have not necessarily given or done all we could. Sometimes, although we help and give to those in need, we falsely deny being able to help more. The Midrash’s account of the plague of darkness perhaps is meant to teach us to be honest about our “possessions,” about our means and our capabilities. If we have resources or talents that can be used to help and contribute, then we must avoid the tendency to deny having them, and instead commit to give and achieve all that we can, to the very best of our ability.
(We should note that the Midrash itself appears to answer this question. It explains that at the time of the Exodus, when Benei Yisrael pproached the Egyptians and named the possessions which they had seen during the plague of darkness, they earned favor in the Egyptians’ eyes by proving their ethical standards. The Egyptians were shown that Benei Yisrael had free access to their homes, and yet, they did not take anything. It is precisely in this way that Benei Yisrael found favor in the Egyptians’ eyes, and they gave them their belongings to take with them out of Egypt.)