A little-known fact about the Israelite’s exodus from Egypt is that many Egyptians went with them.
37 And the children of Israel journeyed from Rameses to Succoth, about six hundred thousand on foot that were men, beside children.
38 And a mixed multitude went up also with them; and flocks, and herds, even very much cattle. (Exodus 12:37-38)
A few verses after this record, we read God’s requirements for the annual remembrance of Passover.
43 And YHVH said unto Moses and Aaron, This is the ordinance of the passover: There shall no stranger eat thereof:
44 But every man’s servant that is bought for money, when thou hast circumcised him, then shall he eat thereof.
45 A foreigner and an hired servant shall not eat thereof.
46 In one house shall it be eaten; thou shalt not carry forth ought of the flesh abroad out of the house; neither shall ye break a bone thereof.
47 All the congregation of Israel shall keep it.
48 And when a stranger shall sojourn with thee, and will keep the passover to YHVH, let all his males be circumcised, and then let him come near and keep it; and he shall be as one that is born in the land: for no uncircumcised person shall eat thereof.
49 One law shall be to him that is homeborn, and unto the stranger that sojourneth among you. (Exodus 12:43-49)
The Egyptians who wanted to celebrate the Lord’s Passover alongside the native-born Israelites could do so as long as they underwent circumcision.
Other rules in Israel applied to both native-born Israelites and aliens alike.
Neither could eat blood.
10 And whatsoever man there be of the house of Israel, or of the strangers that sojourn among you, that eateth any manner of blood; I will even set my face against that soul that eateth blood, and will cut him off from among his people. (Leviticus 17:10)
They could not eat meat that had not been slaughtered appropriately.
13 And whatsoever man there be of the children of Israel, or of the strangers that sojourn among you, which hunteth and catcheth any beast or fowl that may be eaten; he shall even pour out the blood thereof, and cover it with dust.
14 For it is the life of all flesh; the blood of it is for the life thereof: therefore I said unto the children of Israel, Ye shall eat the blood of no manner of flesh: for the life of all flesh is the blood thereof: whosoever eateth it shall be cut off.
15 And every soul that eateth that which died of itself, or that which was torn with beasts, whether it be one of your own country, or a stranger, he shall both wash his clothes, and bathe himself in water, and be unclean until the even: then shall he be clean.
16 But if he wash them not, nor bathe his flesh; then he shall bear his iniquity. (Leviticus 17:13-16)
They were not to worship the god Molech.
2 Again, thou shalt say to the children of Israel, Whosoever he be of the children of Israel, or of the strangers that sojourn in Israel, that giveth any of his seed unto Molech; he shall surely be put to death: the people of the land shall stone him with stones.
3 And I will set my face against that man, and will cut him off from among his people; because he hath given of his seed unto Molech, to defile my sanctuary, and to profane my holy name.
4 And if the people of the land do any ways hide their eyes from the man, when he giveth of his seed unto Molech, and kill him not:
5 Then I will set my face against that man, and against his family, and will cut him off, and all that go a whoring after him, to commit whoredom with Molech, from among their people. (Leviticus 20:2-5)
They were not to bring defective offerings.
18 Speak unto Aaron, and to his sons, and unto all the children of Israel, and say unto them, Whatsoever he be of the house of Israel, or of the strangers in Israel, that will offer his oblation for all his vows, and for all his freewill offerings, which they will offer unto the Lord for a burnt offering;
19 Ye shall offer at your own will a male without blemish, of the beeves, of the sheep, or of the goats.
20 But whatsoever hath a blemish, that shall ye not offer: for it shall not be acceptable for you. (Leviticus 22:18-20)
They were not to curse God.
15 And thou shalt speak unto the children of Israel, saying, Whosoever curseth his God shall bear his sin.
16 And he that blasphemeth the name of the Lord, he shall surely be put to death, and all the congregation shall certainly stone him: as well the stranger, as he that is born in the land, when he blasphemeth the name of the Lord, shall be put to death. (Leviticus 24:15-16)
In fact,
Ye shall have one manner of law, as well for the stranger, as for one of your own country: for I am the Lord your God (Leviticus 24:22).
One ordinance shall be both for you of the congregation, and also for the stranger that sojourneth with you, an ordinance for ever in your generations: as ye are, so shall the stranger be before the Lord. (Numbers 15:15)
Paul says that Gentiles who believe in Jesus the Messiah become fellow citizens with God’s people.
11 Wherefore remember, that ye being in time past Gentiles in the flesh, who are called Uncircumcision by that which is called the Circumcision in the flesh made by hands;
12 That at that time ye were without Christ, being aliens from the commonwealth of Israel, and strangers from the covenants of promise, having no hope, and without God in the world:
13 But now in Christ Jesus ye who sometimes were far off are made nigh by the blood of Christ. (Ephesians 2:11-13)
19 Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God (Ephesians 2:19).