John 1:12

But as many as did receive him, on them he bestowed authority to become children of God, even on those who believe on his name:

Romans 9:25-26

As also he saith in Hosea, "I will call her which was not my people, my people; and her which was not beloved, beloved.

1 Peter 2:10

who in time past were not a people, but are now the people of God; who had not obtained mercy, but are now the objects of mercy.

Treasury of Scripture Knowledge

Summary

For thou hast confirmed to thyself thy people Israel to be a people unto thee for ever: and thou, LORD, art become their God.

Bible References

Art become

John 1:12
But as many as did receive him, on them he bestowed authority to become children of God, even on those who believe on his name:
Romans 9:25
As also he saith in Hosea, "I will call her which was not my people, my people; and her which was not beloved, beloved.
1 Peter 2:10
who in time past were not a people, but are now the people of God; who had not obtained mercy, but are now the objects of mercy.