For as many as are led by the Spirit of God, these are Sons of God. (15) For you did not receive the spirit of bondage again to fear, but you received the Spirit of adoption by whom we cry out “Abba, Father.” (16) The Spirit Himself bears witness with our spirit, that we are children of God, (17) and if children, then heirs – heirs of God and joint heirs with Christ, if indeed we suffer with Him, that we may also be glorified together.
The letter to the Romans was written by the apostle Paul. The theme of chapter 8 is the security of believers – the security of those who accept the offers of the gospel is certain. The whole chapter is a series of arguments to support this one point and the proposition is contained in the first verse; ‘There is now no condemnation to those who are in Christ Jesus, who do not walk according to the flesh, but according to the Spirit.’
Our verses today tells us that believers shall enjoy eternal life not because they have the spirit of life but because they are children of God. Paul uses the word adoption – a very common practice in those ancient days – as a picture of what God has done for us; in our human nature we were condemned but we are children of God by faith in Christ Jesus, not by trusting ourselves or our good works. God first chose us. Our faith doesn’t originate in ourselves. Natural man does not accept things of the Spirit of God which is foolishness to him. Natural man does not understand or seek God but faith is a work of the Spirit in us – it is that inner witness of the Spirit to our spirit that we are God’s child.
It is certain that Jesus will inherit all God has promised and in faith we are fellow heirs with Christ. Our salvation – our inheritance – is secure not because of anything in us but because we are in Christ in faith. Those who love God and to whom the Spirit witnesses that they are children of God cannot doubt that they are indeed His children and know that they are heirs – heirs of God and joint heirs in Christ. The words inherit, heirs, inheritance are all through the Bible because possession by inheritance is much more secure than that obtained by purchase or another method. Paul here is talking of the right, the certainty, the inalienable character of the possession.