True believers have received a spirit of adoption as sons. Paul is talking about a Spirit-produced awareness of the rich reality that God has made us his children, and, therefore, that we can come before him without fear or hesitation as our beloved Father. In this we have the confidence to cry out, “Abba! Father!” This denotes tenderness, dependence, and a relationship free of fear or anxiety (cf. Mark 14:36).
16 The Spirit Himself testifies with our spirit that we are children of God, 17 and if children, heirs also, heirs of God and fellow heirs with Christ, if indeed we suffer with Him so that we may also be glorified with Him. Romans 8:16-17 (NASB)
Even through as Christians we are justified and are under no condemnation (Romans 8:1) it is also clearly taught in God’s Word that Christians are to live lives of repentance from the works of the flesh. There are some, such as those who call themselves “New Calvinists” who take the Doctrines of Grace and separate them from the great teachings of the Puritans such as John Owen, John Bunyan, Thomas Watson, Jonathan Edwards, et cetera that made it clear that in this life Christians are required to “work out their salvation with fear and trembling” (Philippians 2:12). No, these “New Calvinists are antinomians in that they teach those who follow them that if they are in Christ, what they do in the flesh is merely for their enjoyment and has no eternal consequences. Really? Is that what God’s Word says?
12 So then, brethren, we are under obligation, not to the flesh, to live according to the flesh— 13 for if you are living according to the flesh, you must die; but if by the Spirit you are putting to death the deeds of the body, you will live. 14 For all who are being led by the Spirit of God, these are sons of God. 15 For you have not received a spirit of slavery leading to fear again, but you have received a spirit of adoption as sons by which we cry out, “Abba! Father!” 16 The Spirit Himself testifies with our spirit that we are children of God, 17 and if children, heirs also, heirs of God and fellow heirs with Christ, if indeed we suffer with Him so that we may also be glorified with Him. Romans 8:12-17 (NASB)
To live according to the flesh is to be an unbeliever. However, to live by the Spirit means that you are a believer, that is, you are in Christ and He is in you. The flesh is our unredeemed humanness—that complex of sinful passions that sin generates through its one remaining domain—our bodies (Romans 6:6, 12; 7:5). In v13 we learn what believers must do in the struggle with sin. Paul makes it clear that there are some false teaching in the Church about how believers are made holy and he destroys those teachings right here. The first false view is that in a crisis-moment we are immediately made perfect. The second false view is that we must “let God” take over while we remain idle. The third false view is that some turning-point decision will propel us to a higher level of holiness. Instead, Paul tells us that that the Holy Spirit provides us with the energy and power to continually and gradually be killing our sins, a process never completed in this life. The means the Holy Spirit uses to accomplish this process is our faithful obedience to the simple commands of Sacred Scripture (Ephesians 5:18; Colossians 3:16; 13:14; Psalm 1:2; 119:11; Luke 22:40; John 17:17; 1 Corinthians 6:18; 9:25-27; 1 Peter 2:11).
