Exodus 23:19. Thou shalt not seethe a kid in his mother’s milk.
As this injunction is put in connection with sacrifices and festivals, it seems to have referred to some idolatrous practices of the heathen. Cudworth says, on the authority of an ancient Karaite Comment on the Pentateuch, that it was an ancient heathen custom to boil a kid in the dam’s milk, and then besprinkle with it all the trees, fields, gardens and orchards. This was done at the close of their harvests for the purpose of making trees and fields more fruitful the following year. It will be noticed that the injunction of the text is given in connection with the feast of harvest.
Thomson says, that the Arabs “select a young kid, fat and tender, dress it carefully, and then stew it in milk, generally sour, mixed with onions and hot spices such as they relish. They call it Lebnimmu in his mother’s milk. The Jews, however, will not eat it” (The Land and the Book, vol.1, 135).