The prohibition against seething a kid in its mother’s milk appears three times in the Bible, in two very different contexts. In Exodus, it appears twice in discussions of agricultural practices; in Deuteronomy, it is the last item in a list of animals considered unfit for human consumption. None of the contexts seems relevant to the prohibition, leading author Jack Sasson to speculate about its original meaning and intent.
Exodus 23:19
You will bring the best of your land’s early harvest to the Temple of the Lord, your God. You will not seethe a kid in its mother’s milk.
Exodus 34:26
You will bring the best of your land’s early harvest to the Temple of the Lord, your God. You will not seethe a kid in its mother’s milk.
Deuteronomy 14:21
You will not partake of naturally dead animals. You may give it to a resident foreigner who may eat it or you may sell it to a foreigner, for you belong to a people sanctified by the Lord. You will not seethe a kid in its mother’s milk.