Romans is the foundation of the seven Church Epistles and comes first in the order of the three doctrinal epistles, the others being Ephesians and Thessalonians.
The main subject is the revelation of God’s wrath against sin and of the only ground upon which the sinner can stand in righteousness before Him. It shows both Jew and Gentile falling short of the standard of God’s glory in their attempts to effect their own righteousness, and their need for a divine righteousness.
Romans reveals what God has done with sins and with sin and how the Christian, as a saved sinner, rescued from the depths of sin and iniquity, is individually justified simply by his trust in and acceptance of the finished work of Jesus Christ, and how he is united with him (in identification) in death, burial and resurrection.
Romans teaches that although the Christian’s sin nature continues with him in constant hostility to the “new man,” he can reckon the “old man” dead and walk in newness of life.
A Christian’s foundation is that he has been judged righteous in God’s sight, that there is no condemnation from God and that nothing can separate him from God’s love. Thus, he sees that his human frailty does not invalidate what God has done for him and in him, and that he can refuse to condemn himself. Instead, he is to be transformed, thought by thought, by the renewing of his mind to the end that he functions as a unique member of the Body of Christ and walks honestly before all men, showing them by his words and works God’s abounding goodness and love.