John Gill's Exposition of the Whole Bible
Isaiah 32:6
For the vile person will speak villainy,.... Or, "a fool will utter folly" g; a man that has no understanding of Gospel truths himself can not deliver them to others; he will only speak foolish things, concerning the purity of human nature, the power of man's free will, the sufficiency of his own righteousness to justify him, and the merits of good works, and the like; and therefore such a man is a very improper one to be a guide and governor in the church of God:
and his heart will work iniquity; forge and devise it within himself; will form schemes of false doctrine, discipline, and worship, disagreeable to the word of God:
to practise hypocrisy; to make men believe he is a very devout and religious man, when he has no good thing in him, and to put others upon a profession of religion that have none; which things are commonly done by foolish and ignorant preachers:
and to utter error against the Lord; such doctrines as are contrary to the free, rich, sovereign grace of God; to the deity, personality, sonship, offices, blood, sacrifice, and righteousness of Christ, and so to the person and operations of the blessed Spirit:
to make empty the soul of the hungry; and he will cause the drink of the thirsty to fail; the "hungry" and "thirsty" are such as hunger and thirst after, and earnestly desire, the sincere milk of the word for their spiritual nourishment and growth; whose "souls" become "empty", and their "drink" fails, when the doctrines of grace are not dispensed unto them, but false and unedifying doctrines are delivered, so that their souls sink and faint, and are ready to die away, for want of the bread of the Gospel; agreeably to this sense, the Targum paraphrases the words thus,
"to make the soul of the righteous weary, who desire doctrine, as a hungry man bread; and the words of the law, which are as water to him that is thirsty, they think to cause to cease.''
g כי נבל נבלה ידבר "nam stultus stultitiam loquetur", Pagninus, Montanus.