Rom 15:16, 1 Pt 2:5,9
In the Old Testament, God said that He would bring the people of Israel who were scattered throughout the nations to the holy land and make them priests to offer gifts to God. (Isa 66:20)
Isa 66:20 And they shall bring all your brethren for an offering unto the Lord out of all nations upon horses, and in chariots, and in litters, and upon mules, and upon swift beasts, to my holy mountain Jerusalem, saith the Lord, as the children of Israel bring an offering in a clean vessel into the house of the Lord.
God has given us the duty of priests of the gospel of God to preach the gospel to the Gentiles and to offer the Gentiles as sacrifices to God. (Romans 15:16, 1 Peter 2:5,9)
Romans 15:16 That I should be the minister of Jesus Christ to the Gentiles, ministering the gospel of God, that the offering up of the Gentiles might be acceptable, being sanctified by the Holy Ghost.
1 Peter 2:5 Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ. 9 But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light;