Exodus 12:45

It is a night to be much observed to the LORD for bringing them out from the land of Egypt. This is that night of the LORD, to be much observed by all the children of Israel throughout their generations.

The LORD said to Moses and Aaron, “This is the ordinance of the Passover. No foreigner shall eat of it,

but every man’s servant who is bought for money, when you have circumcised him, then shall he eat of it.

It must be eaten in one house. You shall not carry any of the meat outside of the house. Do not break any of its bones.

All the congregation of Israel shall keep it.

When a stranger lives as a foreigner with you, and would like to keep the Passover to the LORD, let all his males be circumcised, and then let him come near and keep it. He shall be as one who is born in the land; but no uncircumcised person shall eat of it.