In whose spirit there is no guile. In this clause the Psalmist distinguishes believers both from hypocrites and from senseless despisers of God, neither of whom care for this happiness, nor can they attain to the enjoyment of it. The wicked are, indeed, conscious to themselves of their guilt, but still they delight in their wickedness; harden themselves in their impudence, and laugh at threatenings; or, at least, they indulge themselves in deceitful flatteries, that they may not be constrained to come into the presence of God. Yea, though they are rendered unhappy by a sense of their misery, and harassed with secret torments, yet with perverse forgetfulness they stifle all fear of God. As for hypocrites, if their conscience as any time stings them, they soothe their pain with ineffectual remedies: so that if God at any time cite them to his tribunal, they place before them I know not what phantoms for their defense; and they are never without coverings whereby they may keep the light out of their hearts. Both these classes of men are hindered by inward guile from seeking their happiness in the fatherly love of God. Nay more, many of them rush frowardly into the presence of God, or puff themselves up with proud presumption, dreaming that they are happy, although God is against them. David, therefore, means that no man can taste what the forgiveness of sins is until his heart is first cleansed from guile. What he means, then, by this term, guile, may be understood from what I have said. Whoever examines not himself, as in the presence of God, but, on the contrary, shunning his judgment, either shrouds himself in darkness, or covers himself with leaves, deals deceitfully both with himself and with God. It is no wonder, therefore, that he who feels not his disease refuses the remedy. The two kinds of this guile which I have mentioned are to be particularly attended to. Few may be so hardened as not to be touched with the fear of God, and with some desire of his grace, and yet they are moved but coldly to seek forgiveness. Hence it comes to pass, that they do not yet perceive what an unspeakable happiness it is to possess God's favor. Such was David's case for a time, when a treacherous security stole upon him, darkened his mind, and prevented him from zealously applying himself to pursue after this happiness. Often do the saints labor under the same disease. If, therefore, we would enjoy the happiness which David here proposes to us, we must take the greatest heed lest Satan, filling our hearts with guile, deprive us of all sense of our wretchedness, in which every one who has recourse to subterfuges must necessarily pine away.

Blessed is the man unto whom the Lord imputeth not iniquity - Whose sin is not "reckoned" to him, or "charged" on him. The reference here is "to his own sin." The idea is not, that he is happy on whom God does not charge the guilt of other men, but that he is happy who is not charged "with his own guilt," or who is treated as if he had no guilt; that is, as if he were innocent. This is the true idea of justification. It is, that a man, although he is a sinner, and "is conscious" of having violated the law of God, is treated as if he had not committed sin, or as if he were innocent; that is, he is pardoned, and his sins are remembered against him no more; and it is the purpose of God to treat him henceforward as if he were innocent. The act of pardon does not change the facts in the case, or "make him innocent," but it makes it proper for God to treat him as if he were innocent. The sin will not be re-charged upon him, or reckoned to his account; but he is admitted to the same kind of treatment to which he would be entitled if he had always been perfectly holy. See Romans 1:17, note; Romans 3:24, note; Romans 4:5, note; Romans 5:1, note.
And in whose spirit there is no guile - Who are sincere and true. That is, who are not hypocrites; who are conscious of no desire to cover up or to conceal their offences; who make a frank and full confession to God, imploring pardon. The "guile" here refers to the matter under consideration. The idea is not who are "innocent," or "without guilt," but who are sincere, frank, and honest in making "confession" of their sins; who keep nothing back when they go before God. We cannot go before him and plead our innocence, but we may go before him with the feeling of conscious sincerity and honesty in making confession of our guilt. Compare Psalm 66:18.

Blessed is the man to whom the Lord imputeth not iniquity,.... Or "does not think of it" (n); with respect unto men, at least to the harm of them; his thoughts are thoughts of peace, and not of evil; their sins and iniquities he remembers no more; he does not charge them with them, he does not reckon them, or place them to their account, having imputed them to his Son; see 2-Corinthians 5:19. The Apostle Paul interprets this as inclusive of the imputation of righteousness without works; even of the righteousness of Christ, in which the blessedness of a man lies, Romans 4:6; for such an one is accepted with God, is justified in his sight, and is secure from condemnation and wrath; it is well with him at all times, in life, at death, and at judgment; he is an heir of eternal life, will enter into it, and be for ever glorified;
and in whose spirit there is no guile: for being thoroughly convinced of sin, he is sincere in his repentance for it, without deceit and hypocrisy in his confession of it; as David, the Apostle Paul, and the publican were, when they acknowledged themselves sinners; his faith, in looking to Christ for pardon and righteousness, is from the heart, and is unfeigned, and so is his profession of it before God, angels, and men; and whatever hypocrisy and guile are remaining in the old man, there is none in the new spirit put into him; in the new man, which is created in him, and which sinneth not: as the other phrases are expressive of pardon and justification, this points at internal sanctification, and which serves to complete the description of the happy man; such an one as David himself was; and this happiness he illustrates from his own experience in the following verses.
(n) "cogitat", Piscator; "cogitando reputavit", Gejerus; so Ainsworth.

imputeth--charge to him, and treat him accordingly.
no guile--or, deceit, no false estimate of himself, nor insincerity before God (compare Romans 8:1).

Imputeth - Whom God doth not charge with the guilt of his sins, but graciously pardons and accepts him in Christ. No guile - Who freely confesses all his sins, and turns from sin to God with all his heart.