Audio commentary on this verse

Note 31 at Rom. 8:15: This spirit of bondage is a reference to the old sin nature (see note 9 at Rom. 5:21, p. 775). The fact that Paul says, "ye have not received the spirit of bondage again . . ." is a further testimony that our old sin nature is not just ceremonially dead but that it is gone in the life of the believer (see note 3 at Rom. 6:2, p. 776).

Note 32 at Rom. 8:15: We are sons of God by adoption. Jesus was the Son of God by nature. As Jesus said to the Jews, we were of our Father the devil (Jn. 8:44; Eph. 2:3), but Jesus purchased us and made us adopted sons of God.