51 It is said, in fact, that there is among you a sin of the flesh, such as is not seen even among the Gentiles, that one of you has his father's wife. 2 And in place of feeling sorrow, you are pleased with yourselves, so that he who has done this thing has not been sent away from among you. 3 For I myself, being present in spirit though not in body, have come to a decision about him who has done this thing;
Matthew Henry's Commentary on 1 Corinthians 5:1-3
Commentary on 1 Corinthians 5:1-8
(Read 1 Corinthians 5:1-8)
The apostle notices a flagrant abuse, winked at by the Corinthians. Party spirit, and a false notion of Christian liberty, seem to have saved the offender from censure. Grievous indeed is it that crimes should sometimes be committed by professors of the gospel, of which even heathens would be ashamed. Spiritual pride and false doctrines tend to bring in, and to spread such scandals. How dreadful the effects of sin! The devil reigns where Christ does not. And a man is in his kingdom, and under his power, when not in Christ. The bad example of a man of influence is very mischievous; it spreads far and wide. Corrupt principles and examples, if not corrected, would hurt the whole church. Believers must have new hearts, and lead new lives. Their common conversation and religious deeds must be holy. So far is the sacrifice of Christ our Passover for us, from rendering personal and public holiness unnecessary, that it furnishes powerful reasons and motives for it. Without holiness we can neither live by faith in him, nor join in his ordinances with comfort and profit.