Exodus 34:24 (KJV)

All that openeth the matrix is mine; and every firstling among thy cattle, whether ox or sheep, that is male.

But the firstling of an ass thou shalt redeem with a lamb: and if thou redeem him not, then shalt thou break his neck. All the firstborn of thy sons thou shalt redeem. And none shall appear before me empty.

Six days thou shalt work, but on the seventh day thou shalt rest: in earing time and in harvest thou shalt rest.

And thou shalt observe the feast of weeks, of the firstfruits of wheat harvest, and the feast of ingathering at the year's end.

Thrice in the year shall all your menchildren appear before the LORD God, the God of Israel.

Thou shalt not offer the blood of my sacrifice with leaven; neither shall the sacrifice of the feast of the passover be left unto the morning.

The first of the firstfruits of thy land thou shalt bring unto the house of the LORD thy God. Thou shalt not seethe a kid in his mother's milk.

And the LORD said unto Moses, Write thou these words: for after the tenor of these words I have made a covenant with thee and with Israel.

And he was there with the LORD forty days and forty nights; he did neither eat bread, nor drink water. And he wrote upon the tables the words of the covenant, the ten commandments.

And it came to pass, when Moses came down from mount Sinai with the two tables of testimony in Moses' hand, when he came down from the mount, that Moses wist not that the skin of his face shone while he talked with him.