Genesis 6:20

20 Two of every kind of bird, of every kind of animal and of every kind of creature that moves along the ground will come to you to be kept alive.

Read Genesis 6:20 Using Other Translations

Of fowls after their kind, and of cattle after their kind, of every creeping thing of the earth after his kind, two of every sort shall come unto thee, to keep them alive.
Of the birds according to their kinds, and of the animals according to their kinds, of every creeping thing of the ground, according to its kind, two of every sort shall come in to you to keep them alive.
Pairs of every kind of bird, and every kind of animal, and every kind of small animal that scurries along the ground, will come to you to be kept alive.

What does Genesis 6:20 mean?

John Gill's Exposition of the Bible
Genesis 6:20

Of fowls after their kind, and of cattle after their kind,
of every creeping thing of the earth after his kind
What before is generally expressed by "every living thing", is here particularly explained of every sort of them; and from the order of them some have thought that in the same manner they were disposed of in the ark, the fowls in the first story, the cattle in the next, and the creeping things in the lowermost: but others place them in a different manner, (See Gill on Genesis 6:16) the roots and grain in the lower story, the living creatures of all sorts in the second, and their hay and litter in the third: the second story being three hundred cubits long, and fifty broad, contained in the whole fifteen thousand cubits, which is supposed to be divided into an hundred and fifty equal rooms; so the Targum of Jonathan on ( Genesis 6:14 ) of these, four are allowed for Noah and his family, two with earth for those animals that live underground, one for those which live on herbs and roots, and the other for those which live on flesh; and the other one hundred and forty four rooms are divided into three parts, that is, twenty four for birds, twenty five for beasts, and the other ninety five for such animals as are designed to be food for the rest; and according to the calculations of learned men, there appear to have been in this story rooms sufficient for all sorts of birds, beasts, and creeping things {k}: two of every sort shall come unto thee, to keep them alive;
that is, they shall come of themselves, as Jarchi and Aben Ezra observe, the providence of God so directing and impelling them, just as the creatures came to Adam; so that there was no need for Noah to take any pains by hunting or hawking to get such a number together: the Targum of Jonathan is,

``they shall come unto thee by the hand of an angel, who shall take and cause them to come.''
So says another Jewish F12 writer, that they were collected by the angels who presided over each species; in which, except the notion of angels presiding over every kind of creature, there is no incongruity, as Bishop Patrick observes; and two of every sort were to come to the ark, to be preserved alive there, that they might propagate their species. So Lucian says F13, that swine, and horses, and lions, and serpents, and all other creatures which were on the earth, entered into the ark "by pairs".
FOOTNOTES:

F11 Vid. Bedford's Scripture Chronology, c. 12. p. 155.
F12 Pirke Eliezer, c. 23.
F13 De Dea Syria.
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