1 Corinthians 7:21-22

7:21 Were you called as a slave? Do not worry about it. But if indeed you are able to be free, make the most of the opportunity. 7:22 For the one who was called in the Lord as a slave is the Lord’s freedman. In the same way, the one who was called as a free person is Christ’s slave.

Galatians 3:28

3:28 There is neither Jew nor Greek, there is neither slave nor free, there is neither male nor female – for all of you are one in Christ Jesus.

Colossians 3:11

3:11 Here there is neither Greek nor Jew, circumcised or uncircumcised, barbarian, Scythian, slave or free, but Christ is all and in all.