And Abraham took Ishmael his son, and all that were born in his house, and all that were bought with his money, every male among the men of Abraham's house; and circumcised the flesh of their foreskins in the same day, as God had said unto him.
And when a foreigner shall sojourn with you, 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 of it.
Circumcise yourselves to the LORD, and take away the foreskins of your heart, you men of Judah and inhabitants of Jerusalem: lest my fury come forth like fire, and burn that none can quench it, because of the evil of your doings.
And he gave him the covenant of circumcision: and so Abraham begat Isaac, and circumcised him the eighth day; and Isaac begat Jacob; and Jacob begat the twelve patriarchs.
Whom God has set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;
As many as desire to make a fair show in the flesh, they constrain you to be circumcised; only lest they should suffer persecution for the cross of Christ.
Therefore remember, that you 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;
And the LORD your God will circumcise your heart, and the heart of your descendants, to love the LORD your God with all your heart, and with all your soul, that you may live.
And this is the reason why Joshua did circumcise: All the people that came out of Egypt, that were males, even all the men of war, died in the wilderness by the way, after they came out of Egypt.