Genesis 9:3 - Matthew Poole's English Annotations on the Holy Bible

Every moving thing which is wholesome and fit for food, and clean; an exception to be gathered both from the nature of the thing, and from the distinction of clean and unclean beasts, mentioned before and afterwards. That liveth. This is added to exclude the use of those creatures which either died of themselves, or were killed by wild beasts, which is here forbidden implicitly, and afterwards expressly. See Exodus 22:31 Leviticus 22:8. Shall be meat for you: it is not a command that we must, but a permission that we may eat of them. A grant possibly given before the flood, but now expressed, either because the former allowance might seem to be forfeited, or because as men now grew more infirm and needed better nourishment, so the earth was grown more feeble by the flood, and its fruits yielded less and worse nourishment. I have given you all things: understand this with the limitation above-mentioned. The green herbs were given before, Genesis 1:29.