Taken from Dr. Constable’s notes on Deuteronomy:
“The ceremonial custom of boiling a kid in its mother’s milk is known from the ancient Canaanite tablets found at Ugarit [i.e., the Ras Shamra Tablets]. Such a rite was superstitiously observed by the Canaanites, hoping that through magical acts they could increase fertility and productivity (14:21; Ex. 23:19; 34:26).”
“. . . various Canaanite cults regularly engaged in the practices of seething a kid in its mother’s milk as a fertility rite of sympathetic magic intended to coerce the deity into granting fertility to the wives, fields, and flocks of the cults’
adherents. Such rites of sympathetic magic ‘worked’ on the premise that the gods were in some way part of and subject to the same natural created order that human beings also inhabited. By finding the common natural connection points, human beings could ‘push the right buttons’ and thus manipulate the gods . . .
“Israelites do not, through an act of sympathetic magic, try to
coerce the deity into blessing them with fertility for the year to come; but instead, after the year’s crops have been harvested and whether that year’s harvest has been fruitful or not, Israelites bring a tithe to God as an act of gratitude [cf. vv. 22-29].” 162
Samuel J. Schultz, Deuteronomy, p. 55.
Michael L. Goldberg, “The Story of the Moral: Gifts or Bribes in Deuteronomy?” Interpretation 38:1 (January 1984):21-22.