“For My part, I am about to bring the Flood—waters upon the earth—to destroy all flesh under the sky in which there is breath of life; everything on earth shall perish.
מבול A FLOOD — so called because it ruined (בלה) everything; because it cast everything into confusion (בלל), and because it brought (הוביל from root יבל) everything down from the heights to a lower level. And this last explanation underlies the translation of Onkelos who translates it by טופנא (Ar. טוף = Heb. צוף) because the Flood caused everything to float about and brought it (the Ark) to Babel which is a low-lying district. That is the reason why it (Babylon) is called, also, Shinar (שנער): because all those who died through the Flood were shaken out (ננערו) into it (Shabbat 113b).
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God called the expanse Sky. And there was evening and there was morning, a second day.
ויקרא אלהים לרקיע שמים AND GOD CALLED THE EXPANSE HEAVEN — The word “שמים”, Heaven, may be regarded as made up of שא מים “Carry water”, or שם מים “There is water”, or אש ומים “Fire and water”. He mingled fire with water and of them He made the heavens (Chagigah 12a).
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Then יהוה said to Noah, “Go into the ark, with all your household, for you alone have I found righteous before Me in this generation.
ראיתי צדיק [THEE] HAVE I SEEN RIGHTEOUS — It does not say “righteous and wholehearted” (as it does at the beginning of the Sedrah); hence we may infer that only a part of a man’s good qualities should be enumerated in his presence (since here God is speaking to Noah and calls him only “righteous”), but that in his absence the whole of his good qualities may be told (since when the Torah speaks about him in the earlier passage it calls him “righteous and wholehearted”) (Eruvin 18b).
Noah, with his sons, his wife, and his sons’ wives, went into the ark because of the waters of the Flood.
מפני מי המבול BECAUSE OF THE WATERS OF THE FLOOD — (מפני properly means ‘‘from before”) — Noah, also, was of those people who are wanting in faith: he believed and he did not believe that the Flood would come, and he would not enter the Ark until the waters forced him to do so (Genesis Rabbah 32:6).