| Matthew Henry's Concise Commentary 66:13-20 We should declare unto those that fear God, what he has done for our souls, and how he has heard and answered our prayers, inviting them to join us in prayer and praise; this will turn to our mutual comfort, and to the glory of God. We cannot share these spiritual privileges, if we retain the love of sin in our hearts, though we refrain from the gross practice, Sin, regarded in the heart, will spoil the comfort and success of prayer; for the sacrifice of the wicked is an abomination of the Lord. But if the feeling of sin in the heart causes desires to be rid of it; if it be the presence of one urging a demand we know we must not, cannot comply with, this is an argument of sincerity. And when we pray in simplicity and godly sincerity, our prayers will be answered. This will excite gratitude to Him who hath not turned away our prayer nor his mercy from us. It was not prayer that fetched the deliverance, but his mercy that sent it. That is the foundation of our hopes, the fountain of our comforts; and ought to be the matter of our praises.
Pulpit CommentaryVerse 18. - If I regard iniquity in my heart, the Lord will not hear me. This is the inward conviction of every simple, unsophisticated soul. It is confirmed by numerous passages of Holy Writ (Job 27:9; Job 31:27; Proverbs 15:29; Proverbs 28:9; Isaiah 1:15; Zechariah 7:13; John 9:31, etc.).
Gill's Exposition of the Entire BibleIf I regard iniquity in my heart,.... There was iniquity in his heart, as there is in every good man's heart, and a great deal too; it is full of it; and it should be regarded in some sense, so as to guard against it, and pray to be kept from it, that it may not break forth into action; and so as to loath it, abhor it, and be humbled for it; but not so as to nourish and cherish it, to take delight and pleasure in it: or "if I look upon it" (h), as it may be rendered; that is, with approbation of it, and satisfaction in it, and ordered his conversation according to it; or acted the deceitful and hypocritical part in prayer; or had any evil intention in his petitions, to consume on his lusts what he asked for; the Lord will not hear me; for the Lord hears not sinners that delight in sin, and live in it; neither profane sinners nor hypocrites; see John 9:31. (h) "si vidi", Pagninus, Montanus; "si aspexi", V. L. "si conspexi", Gejerus.
Jamieson-Fausset-Brown Bible Commentary18. If I regard iniquity in my heart—literally, "see iniquity with pleasure."
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