Again, regarding circumcision and the stranger:
Exodus 12:43-45,48-49 KJV
And the Lord 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. [48] And when a stranger shall sojourn with thee, and will keep the passover to the Lord , 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.
Strangers had to be circumcised in order to eat the passover. However, they were not required to be circumcised to keep Sabbath:
Exodus 20:10 KJV
But the seventh day is the sabbath of the Lord thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates:
Or to bring an offering:
Leviticus 17:8-9 KJV
And thou shalt say unto them, Whatsoever man there be of the house of Israel, or of the strangers which sojourn among you, that offereth a burnt offering or sacrifice, [9] And bringeth it not unto the door of the tabernacle of the congregation, to offer it unto the Lord ; even that man shall be cut off from among his people.
Numbers 15:13-16 KJV
All that are born of the country shall do these things after this manner, in offering an offering made by fire, of a sweet savour unto the Lord . [14] And if a stranger sojourn with you, or whosoever be among you in your generations, and will offer an offering made by fire, of a sweet savour unto the Lord ; as ye do, so he shall do. [15] 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 . [16] One law and one manner shall be for you, and for the stranger that sojourneth with you.
Or keep the Day of Atonement:
Leviticus 16:29-31 KJV
And this shall be a statute for ever unto you: that in the seventh month, on the tenth day of the month, ye shall afflict your souls, and do no work at all, whether it be one of your own country, or a stranger that sojourneth among you: [30] For on that day shall the priest make an atonement for you, to cleanse you, that ye may be clean from all your sins before the Lord . [31] It shall be a sabbath of rest unto you, and ye shall afflict your souls, by a statute for ever.
Or eat the tithes:
Deuteronomy 14:28-29 KJV
At the end of three years thou shalt bring forth all the tithe of thine increase the same year, and shalt lay it up within thy gates: [29] And the Levite, (because he hath no part nor inheritance with thee,) and the stranger, and the fatherless, and the widow, which are within thy gates, shall come, and shall eat and be satisfied; that the Lord thy God may bless thee in all the work of thine hand which thou doest.
Strangers were subject to the laws of God:
Leviticus 24:15-16 KJV
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 24:22 KJV
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 25:35 KJV
And if thy brother be waxen poor, and fallen in decay with thee; then thou shalt relieve him: yea, though he be a stranger, or a sojourner; that he may live with thee.
Numbers 19:9-10 KJV
And a man that is clean shall gather up the ashes of the heifer, and lay them up without the camp in a clean place, and it shall be kept for the congregation of the children of Israel for a water of separation: it is a purification for sin. [10] And he that gathereth the ashes of the heifer shall wash his clothes, and be unclean until the even: and it shall be unto the children of Israel, and unto the stranger that sojourneth among them, for a statute for ever.
They kept Pentecost:
Deuteronomy 16:10-11 KJV
And thou shalt keep the feast of weeks unto the Lord thy God with a tribute of a freewill offering of thine hand, which thou shalt give unto the Lord thy God , according as the Lord thy God hath blessed thee: [11] And thou shalt rejoice before the Lord thy God, thou, and thy son, and thy daughter, and thy manservant, and thy maidservant, and the Levite that is within thy gates, and the stranger, and the fatherless, and the widow, that are among you, in the place which the Lord thy God hath chosen to place his name there.
Tabernacles:
Deuteronomy 16:13-15 KJV
Thou shalt observe the feast of tabernacles seven days, after that thou hast gathered in thy corn and thy wine: [14] And thou shalt rejoice in thy feast, thou, and thy son, and thy daughter, and thy manservant, and thy maidservant, and the Levite, the stranger, and the fatherless, and the widow, that are within thy gates. [15] Seven days shalt thou keep a solemn feast unto the Lord thy God in the place which the Lord shall choose: because the Lord thy God shall bless thee in all thine increase, and in all the works of thine hands, therefore thou shalt surely rejoice.
The stranger was to hear and learn and obey the laws of God:
Deuteronomy 31:11-13 KJV
When all Israel is come to appear before the Lord thy God in the place which he shall choose, thou shalt read this law before all Israel in their hearing. [12] Gather the people together, men, and women, and children, and thy stranger that is within thy gates, that they may hear, and that they may learn, and fear the Lord your God, and observe to do all the words of this law: [13] And that their children, which have not known any thing , may hear, and learn to fear the Lord your God, as long as ye live in the land whither ye go over Jordan to possess it.
So circumcision was a bar to eating the passover. Not much else.