Exodus 12:43-51

Then the LORD said to Moses and Aaron, “These are the instructions for the festival of Passover. No outsiders are allowed to eat the Passover meal. But any slave who has been purchased may eat it if he has been circumcised. Temporary residents and hired servants may not eat it. Each Passover lamb must be eaten in one house. Do not carry any of its meat outside, and do not break any of its bones. The whole community of Israel must celebrate this Passover festival. “If there are foreigners living among you who want to celebrate the LORD’s Passover, let all their males be circumcised. Only then may they celebrate the Passover with you like any native-born Israelite. But no uncircumcised male may ever eat the Passover meal. This instruction applies to everyone, whether a native-born Israelite or a foreigner living among you.” So all the people of Israel followed all the LORD’s commands to Moses and Aaron. On that very day the LORD brought the people of Israel out of the land of Egypt like an army.