Romans 6:17–19—Freed from sin to become slaves of righteousness.

As we saw in verse 16, every human being is a slave to either sin or righteousness. It’s worth noting that Paul likely picked up the slavery metaphor from the words of Jesus: “Truly, truly, I say to you, everyone who practices sin is a slave to sin” (John 8:34). And Jesus spoke of himself as the Liberator from sin: “So if the Son sets you free, you will be free indeed” (8:36).

Now Paul rejoices that the believers in Rome have indeed been set free from sin’s mastery and have become slaves of righteousness. The righteousness he speaks of is not the justified standing before God that they received the moment they were saved but rather the righteous lifestyle that leads to sanctification. It is a life lived in submission to the grace of God, which trains us “to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age” (Titus 2:12).

Obedient from the heart
Paul joyfully thanks God for the ability of the Roman believers to obey from the heart, because at their conversion God gave them a new, willing heart that responds to truth. God has called forth voluntary lovers who obey him out of desire, not compulsion. See 6:1–2 and 12:2 for more comments on the believer’s renewed heart and mind.

The Roman Christians learned to obey what Paul refers to as “the standard of teaching to which you were committed.” The Greek word translated “standard” conveys the idea of form or pattern, and here it stands for the core set of instructions for how Christ’s disciples are to live.

The phrase “to which you were committed” says something important about believers’ relationship to this standard of teaching, but the wording could mislead us. Paul is not saying the Roman Christians made a commitment to these core principles, nor is he saying, as some other translations suggest, the teachings were delivered or given to the believers. Rather, he means God committed these believers to the teachings in the sense that he “handed them over to” or “placed them under” the teachings. This expression thus fits with the section’s overall theme of submission—slave to master, obligation “under grace,” now subjection to instruction, and ultimately “slaves of God” (verse 22).

Paul sought to convey the authority of this body of ethical instruction, which has been included in the New Testament and given to believers with the expectation of obedience. In this epistle, chapters 12 and 13 best encapsulate the standard norms that govern how believers are to interact in the church and with the world.

“I am speaking in human terms”
With his opening phrase in verse 19, Paul seems to recognize the inadequacy of using the demeaning institution of slavery to illustrate believers’ relationship to God. Charles Swindoll says, “While the illustration of slavery is powerful, it is flawed in one important respect. The truth Paul labors to teach is really a paradox. Slavery to God is the greatest freedom a human can ever know.”

Impurity and ever-increasing lawlessness
Prior to their conversions the Roman believers gave themselves over to “impurity” (a state of moral filthiness) and to ever-increasing lawlessness. As Everett Harrison puts it, their unsaved condition was “uncleanness within and lawlessness without.” Paul uses the term impurity elsewhere in reference to sexual immorality, as in 1:24, “Therefore God gave them up in the lusts of their hearts to impurity, to the dishonoring of their bodies among themselves.” (For similar uses of this word, see Galatians 5:19, 2 Corinthians 12:21; Ephesians 5:3, and Colossians 3:5).

Paul’s “just as you once presented … so now present” formula exhorts the Roman Christians to now seek righteousness with the same intentionality and fervor they once practiced impurity. Many of us recall what it was like to go places and arrange encounters in anticipation of a sexual experience or other pleasure. Now we ought to apply the same zeal to our practice of righteousness.

In our culture the high value placed on freedom, especially sexual freedom, is one of the main reasons people reject biblical teaching. The answer of Paul is that this quest for freedom is illusory, that it leads to captivity from which there is no escape but through Christ who alone offers true freedom.