Leviticus 20:25

you shall therefore keep yourselves separate by making a distinction between the clean beasts, and the beasts which are unclean; and between the clean birds, and the birds which are unclean; and you shall not pollute yourselves with the beasts, or the birds, or any of the reptiles of the earth which I have distinguished for you, by uncleanness, and you shall be consecrated to Me.