The Hebrew Bible says God told Noah to enter the ark, and that rain would begin in seven days (Genesis 7:4). It does not explain why seven days. The Targum Jonathan does, and the explanation transforms the entire Flood story from divine wrath into a last-ditch act of mercy.
"Behold, I give you space of seven days," God says in the Targum. "If they will be converted, it shall be forgiven them; but if they will not be converted, after a time of days yet seven, I will cause rain to come down." This is not in the Hebrew at all. The translators invented a final ultimatum—seven days of open repentance where the entire Flood could have been called off. Humanity failed the test.
The Targum also explains what happened during those seven days. It was a mourning period for Methuselah, who had just died: "at the time of seven days after the conclusion of the mourning for Methushelach, the Lord beheld, and, lo, the sons of men had not turned." The oldest man in the Bible served as humanity's last shield. While people mourned him, God waited. When the mourning ended and nobody repented, the waters came.
And they came hot. The Hebrew says rain fell for forty days. The Targum says "the waters of the deluge came down hotly from the heavens." This detail appears in rabbinic tradition elsewhere—the idea that the Flood was boiling water, a punishment that matched the sin, since the generation of the Flood had "heated" themselves with sexual immorality.
The Targum names the month as Marchesvan, then pauses to explain that months were previously counted from Tishri, "which was the beginning of the year at the completion of the world." This footnote inside scripture reveals translators wrestling with competing Jewish calendars. Meanwhile, the giants—the Nephilim—"gathered there together with their sons and perturbed" the fountains of the deep, as if they tried to physically fight the Flood. And when the ark's door closed, it was not Noah who shut it. "The Word of the Lord covered over the door of the ark." God Himself, through His Memra, sealed it shut.
And the Lord said to Noah, Enter, thou, and every one of thy house, into the ark; for thee have I seen righteous before me in this generation.
Of all clean cattle take thou seven by seven, male and female, and of all cattle not clean, two (and two), male and female.
But of birds of the heaven, seven by seven, male and female, to preserve from them seed upon the earth.
For, behold, I give you space of seven days; if they will be converted, it shall be forgiven them; but if they will not be converted, after a time of days yet seven, I will cause rain to come down upon the earth forty days and forty nights, and will destroy all bodies of man and of beast upon the earth.
And Noah did according to all that the Lord had commanded him.
And Noah was the son of six hundred years when the deluge of waters was upon the earth.
And Noah entered, with his sons and his wife and the wives of his sons with him, into the ark, from before the waters of the deluge.
Of all cattle clean, and of cattle unclean, of birds, and of whatever creepeth upon the earth,
two and two they entered unto Noah into the ark, male and female, as the Lord had instructed Noah.
And it was at the time of seven days after the conclusion of the mourning for Methushelach, that the Lord beheld, and, lo, the sons of men had not turned. And the waters of the deluge came down hotly from the heavens upon the earth.
In the six-hundredth year of the life of Noah, in the second month, which was the month of Marchesvan, for hitherto the months had been numbered from Tishri which was the beginning of the year at the completion of the world, in the seventeenth day of the month, in that day were all the fountains of the great deep broken up. And the giants were gathered there together with their sons and perturbed them, and afterwards the windows of heaven were opened.
And the rain came down upon the earth forty days and forty nights.
In that same day entered Noah, and Shem, and Cham, and Yapheth, the sons of Noah, and the wife of Noah, and the three wives of his sons with him, into the ark:
they, and every animal after his kind, and all cattle after their kind, and every reptile that creepeth upon the earth after his kind, and every fowl after its kind, every bird which flieth.
And they entered to Noah into the ark, two and two of all flesh in which was the breath of life.
And they coming entered, male and female, of all flesh unto him, as the Lord had instructed him; and the Word of the Lord covered over the door of the ark upon the face thereof.
And there was a flood forty days upon the earth, and the waters were multiplied and bare up the ark, and it was lifted from the earth.
And the waters waxed mighty and increased greatly upon the earth, and the ark went floating upon the face of the waters.
And the waters prevailed greatly upon the earth, and all the high hills which were under the heavens were covered:
fifteen cubits higher did the waters prevail, and the mountains were covered.
And all flesh expired which moveth upon the earth; of fowl, and of cattle, and of wild beasts, and every moving thing that moveth upon the earth, and all the sons of men,
--every thing in whose nostrils was the breath of life, of all on the dry land, died.
And all the bodies of men and of beasts upon the face of the earth, from man to cattle, to creeping thing, and to the fowl which wingeth in the air of heaven, perished from the earth; and Noah only was left, and they who were with him in the ark.
And the waters prevailed upon the earth a hundred and fifty days.
