Deuteronomy 12:22
Even as the roebuck and the hart is eaten, so thou shalt eat them: the unclean and the clean shall eat of them alike. Even as the roebuck and the hart is eaten, so thou shalt eat them: the unclean and the clean shall eat of them alike.
Moses gave this instruction as part of rehearsing for Israel, before crossing the Jordan into the promised land, the laws God had given during the wilderness years. The verse regulates where food animals could be slaughtered: whereas Israel had been required to slaughter animals at the sanctuary, after settling throughout Canaan they could slaughter at home the animals needed for food. Animals formerly set apart for sanctuary service could now be killed and eaten as ordinary food, just as the wild roebuck and hart were eaten.
“The unclean and the clean” means ceremonially clean people and people temporarily made ceremonially unclean who could not eat sacred meat, not clean and unclean kinds of meat. The verse belongs to the instruction on clean and unclean meats also addressed in Leviticus 11. Any permission to eat what one desires is limited by the specific prohibitions given alongside it, so the verse does not permit eating animals designated unclean. The passage grants Noah and the Israelites permission to eat animal food, but it does not mean God permitted eating it in the excessive way practiced by the wicked after the flood.