Example teaches
And shall teach people to do so. In some sense it may be said that whoever openly breaks any commandment teaches others to do the same, for example speaks, and many times louder than precept. In this sense it is plain that every open drunkard is a teacher of drunkenness, and every Sabbath-breaker is constantly teaching his neighbor to profane the day of the Lord. But this is not all. A habitual breaker of the law is seldom content to stop here. He generally teaches other people to do so too, by word as well as example, especially when he hardens his neck and hates to be reproved. Such a sinner soon becomes an advocate for sin. He defends what he is resolved not to forsake. He excuses the sin which he will not leave, and thus directly teaches every sin which he commits.
1771 text
3. And shall teach men so――In some sense it may be said, that whosoever openly breaks any commandment, teaches others to do the same: for example speaks, and many times louder than precept. In this sense it is apparent every open drunkard, is a teacher of drunkenness: every sabbath-breaker is constantly teaching his neighbour, to profane the day of the Lord. But this is not all: an habitual breaker of the law, is seldom content to stop here. He generally teaches other men to do so too, by word as well as example: especially when he hardens his neck, and hateth to be reproved. Such a sinner soon commences an advocate for sin: he defends what he is resolved not to forsake. He excuses the sin which he will not leave, and thus directly teaches every sin which he commits.