1 Corinthians 7:22

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.

1 Corinthians 15:58

15:58 So then, dear brothers and sisters, ¹  be firm. Do not be moved! Always be outstanding in the work of the Lord, knowing that your labor is not in vain in the Lord.

[15:58]  ¹ tn Grk “brothers.” See note on the phrase “brothers and sisters” in 1:10.