But shun profane and vain babblings
The ministry of false teachers is mere babbling; a voice, and nothing else, as the man said of his nightingale; a sound of words, but no solid matter in them; great swelling words of vanity, like large bubbles of water, look big, and make a great noise, but have nothing in them; contain nothing but vain, empty, idle, and trifling stuff; what is unprofitable and unedifying, yea, what is profane, contrary to the nature and perfections of God, and not agreeable to the doctrine which is according to godliness; and being palmed upon the Holy Scriptures, is a profanation of them. And all such wicked and empty prate, and babbling, is to be shunned, avoided, and discouraged, refused, and rejected; and, as much as can be, a stop should be put to it, both by ministers and hearers of the word.
For they will increase unto more ungodliness
meaning either that such babblings, if used and encouraged, will grow more and more profane and wicked; or the persons that use them, the unruly and vain talkers, will grow more daring, bold; and impudent, will wax worse and worse, and from one error will proceed to another, for such seldom stop; and having abused one passage of Scripture, will go on to attack another, and will not cease, till they have wrested the whole Scripture to their own destruction, and that of others.