Exodus 34:26-28 World English Bible (WEB)
26 “You shall bring the first of the first fruits of your ground to the house of Yahweh your God.
“You shall not boil a young goat in its mother’s milk.”
27 Yahweh said to Moses, “Write you these words: for in accordance with these words I have made a covenant with you and with Israel.”
28 He was there with Yahweh forty days and forty nights; he neither ate bread, nor drank water. He wrote on the tablets the words of the covenant, the ten commandments.