Here Paul finishes teaching how Christians must live in light of the righteous standing they have through Jesus Christ. Chapter seven worked out a statement in 7:5, that because Christians still have sin indwelling them, they cannot successfully obey God in their own strength. Chapter eight works out 7:6, that Christians live by the Holy Spirit (note 8:1-4). Unbelievers (“carnally minded,” vv. 5-8) are unable and unwilling to obey the Lord, whereas Christians live because of and through the Holy Spirit (vv. 5-6, 9-11).
How can Christians live Christ-like lives? By depending on the Spirit to continually be “killing” sin in their lives (vv. 12-14). The Spirit’s convincing work in the believer’s heart (vv. 15-17) must compel this “living like Christ” that necessarily involves “killing sin.”
The Spirit continually works in believers as they experience suffering (vv. 18-25) and express their sorrows in praying (vv. 26-27). The “groanings” (v. 26) does not refer to praying in tongues but is a figure of speech expressing the Spirit’s prayers according to God’s will for Christians’ definite needs (v. 27). Though Christians may go through suffering they must remember  God’s sovereign, gracious love for them through their suffering (vv. 28-30) and  that nothing in creation can separate them from God’s love in Christ (vv. 35-39).
Truths to Nail Down and Meditate On
- Those who are justified by God through Christ are those who are being sanctified by God through the Spirit. If there is no fruit of growing Christ-likeness, then most likely there is no justification.
- True Christians kill sin. This is an obligation, Christian, not an option! You cannot be casual or unconcerned about sin: you live in a world that is God’s enemy where there is a devil roaming about and sin within you that wars, tempts, and lures. The Spirit works to make you like Christ, and you must participate in his work!
- When you experience great suffering that is exactly the time you need to seek the Lord more, not less! Christian, God ordains every one of your experiences to make you more like Christ and glorify him.