Romans 6 v 19

Romans 6:19
I speak after the manner of men because of the infirmity of your flesh: for as ye have yielded your members servants to uncleanness and to iniquity unto iniquity; even so now yield your members servants to righteousness unto holiness.


To talk of being “enslaved” to righteousness and to God is not correct in one sense, Paul wrote, because God does not hold His children in bondage. But the word “slavery” appropriately describes an unregenerate person’s relationship to sin and to Satan. So Paul used “slavery” for contrasting the relationship of the believer as well. Before developing this idea further, the apostle in effect apologized for its use—I put this in human terms (lit., “I am speaking in human fashion”)—because you are weak in your natural selves (lit., “your flesh”). Apparently Paul felt that his readers’ spiritual perception was feeble so he used this terminology from human experience. Then he basically repeated the ideas of verses 16-17. Unsaved Romans had offered their bodies to impurity and to ever-increasing wickedness (lit., “lawlessness”; cf. 1:24-27; 6:13). They had voluntarily become enslaved! But Paul exhorted believers now to offer themselves as slaves to righteousness leading to holiness (perfect holiness, as the end of the process [cf. v. 22]) in contrast with their former impurity.
  

Excerpt from:
Walvoord, J. F., Zuck, R. B., & Dallas Theological Seminary. (1983-c1985). The Bible knowledge commentary : An Exposition of the Scriptures. Wheaton, IL: Victor Books.


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