5Now therefore, if you will indeed obey my voice, and keep my covenant, then you shall be my own possession from among all peoples; for all the earth is mine; 6and you shall be to me a kingdom of priests, and a holy nation.' These are the words which you shall speak to the children of Israel." (Exodus 19:5-6)
The Nation of Israel shadows the truth that Yahweh intended from eternity for mankind—a special people, chosen by Him, Who love and obey Him and walk with Him.
As God sovereignly chose Abraham, Isaac, then Jacob, we can learn much about Him through His intentions for and dealings with the nation of Israel.
14If a stranger lives as a foreigner with you, or whoever may be among you throughout your generations, and will offer an offering made by fire, of a sweet savor to Yahweh; as you do, so he shall do. 15For the assembly, there shall be one statute for you, and for the stranger who lives as a foreigner [with you], a statute forever throughout your generations: as you are, so shall the foreigner be before Yahweh. 16One law and one ordinance shall be for you, and for the stranger who lives as a foreigner with you. (Numbers 15:14-16)
When Yahweh first chose to make a nation bearing His Name, He had great plans for the world. He envisioned a nation of priests, of those set apart unto Him, who would witness about the true God through both their lifestyles as well as their words. God wanted to reveal Himself through an assembly of people. This assembly was to be known as the Nation of Israel. Its citizens were made up two groups: those who were descendents of Jacob (Israel), and those from other descent who lived with the Israelites. Thus, the Nation of Israel was, from the beginning, destined to be a nation without prejudice—anyone who feared Yahweh and chose to serve Him would be accepted into the Assembly of Israel.
3Neither let the foreigner, who has joined himself to Yahweh, speak, saying, Yahweh will surely separate me from his people; neither let the eunuch say, Behold, I am a dry tree. 4For thus says Yahweh of the eunuchs who keep my Sabbaths, and choose the things that please me, and hold fast my covenant: 5To them will I give in my house and within my walls a memorial and a name better than of sons and of daughters; I will give them an everlasting name, that shall not be cut off. 6Also the foreigners who join themselves to Yahweh, to minister to him, and to love the name of Yahweh, to be his servants, everyone who keeps the Sabbath from profaning it, and holds fast my covenant; 7even them will I bring to my holy mountain, and make them joyful in my house of prayer: their burnt offerings and their sacrifices shall be accepted on my altar; for my house shall be called a house of prayer for all peoples. (Isaiah 56:3-7)
We see that the Lord had to make it clear, many hundreds of years after creating the Nation of Israel, that those from other nations who joined themselves to Yahweh, were not to be valued less than the natives of Israel. Anyone who served God, keeping His Covenant, guarding the sanctity of the Sabbath, and loving the Name of Yahweh, had their sacrifices accepted upon the altar.
These testimonies contain hidden revelations that were fully exposed through the coming of Christ and the teaching of His apostles and prophets. We can learn much about what it means to be part of Yahweh's Assembly by looking to the nation of Israel and to that unto which it pointed.