Romans 6:19

‘I speak after the manner of men because of the infirmity of your flesh. For as you presented your members as servants to uncleanness and to iniquity unto iniquity, even so now present your members as servants to righteousness unto sanctification.'

Paul then points out that they must not take his illustrations too literally, always a danger with certain types of people. He was using illustrations from life to depict spiritual situations, and depicting sin as though it were a slave-master. And he was doing it because they might not be able to understand anything put more deeply. The development of a spiritual mind could take time. Thus he was speaking in terms of life as they knew it (most of them were slaves or servants, and a few were masters) so that they would understand.

He therefore clarifies exactly what he has meant. They had previously presented their members as servants to uncleanness, and to continuing iniquity. Now therefore they are to present their members as servants to righteousness, to cleanness and continuing goodness, resulting in their being made holy and set apart to God as God works within them. ‘Sanctification' means ‘making holy, setting a man apart as separate to God and His ways' and so in the end ‘making Godlike'. Just as the reception of the free gift of righteousness results in justification (Romans 5:16), so does the submission of our members as servants of righteousness result in sanctification, as God responds to our submission with the sanctifying work of the Holy Spirit (Romans 5:1; 2 Corinthians 3:18).