Hans Denck (c.1500-1527) was an early figure in the German Anabaptist movement who combined medieval mysticism with the radical sacramental theologies of Andreas Bodenstein von Karlstadt and Thomas Müntzer. He found that many converts were seeking to broaden the principle established by Paul in 1 Cor 7:18-20 allowing new Christians to maintain their marital status. Concerned, he sought to limit this application, arguing that it is not appropriate to use this passage as a means to justify continuing in sinful patterns of life. Instead, the calling of a believer’s life in the world must be consistent with the calling of Christ and his word.
1 Cor. 7:18-20
Was a man already circumcised when he was called? He should not become uncircumcised. Was a man uncircumcised when he was called? He should not be circumcised. Circumcision is nothing and uncircumcision is nothing. Keeping God’s commands is what counts. Each person should remain in the situation they were in when God called them.
Commentary on 1 Cor. 7:18-20
Woe, woe, thrice woe on those perverse people who know the mind of their Lord yet do not do it and who still want to be justified. Oh, it shall be far more unbearable for them than for those from whom it was partly hidden. Is it not shame upon shame that we desire to know Christ yet hold on to our godless nature nonetheless? We even excuse ourselves with the saying of Paul who bid everyone remain in the calling to which he was called. The sense would be as follows: If the Lord were to call one [who lives] in adultery, he should remain in it. Why then did Matthew not stay in the customs house? Indeed, in our opinion the fishermen were wrong when they left their work. This is what happens to us when we pick up fragments of Scripture and mend the old coat with a new patch. What Paul intended to say about married and single people we like to apply to our useless handiwork, our marketing, usury, and offices. This cannot be.
1 Corinthians, ed. Scott M. Manetsch, Reformation Commentary on Scripture, N.T. vol. 9a, 144-45.