Of every clean beast you shall receive and take with you seven pairs, the male and his mate, and of beasts that are not clean a pair of each kind, the male and his mate, [Lev. 11.]
And Noah built an altar to the Lord and took of every clean [four-footed] animal and of every clean fowl or bird and offered burnt offerings on the altar.
The priests shall teach My people the difference between the holy and the common or profane, and cause them to distinguish between the unclean and the clean.