Behold, thou {f} desirest truth in the inward parts: and in the hidden part thou shalt make me to know wisdom.

(f) He confesses that God who loves pureness of heart, may justly destroy man, who by nature is a sinner much more him whom he had instructed in his heavenly wisdom.

Wesley's Notes

51:6 Truth - Uprightness of heart; and this may be added; as an aggravation of the sinfulness of original corruption, because it is contrary to the holy nature and will of God, which requires rectitude of heart: and, as an aggravation of his actual sin, that it was committed against that knowledge, which God had wrote in his heart.

Jamieson-Fausset-Brown Bible Commentary

6. thou shalt make, &c.-may be taken to express God's gracious purpose in view of His strict requisition; a purpose of which David might have availed himself as a check to his native love for sin, and, in not doing so, aggravated his guilt.

truth . and .wisdom-are terms often used for piety (compare Job 28:28; Ps 119:30).

Matthew Henry's Concise Commentary

51:1-6 David, being convinced of his sin, poured out his soul to God in prayer for mercy and grace. Whither should backsliding children return, but to the Lord their God, who alone can heal them? he drew up, by Divine teaching, an account of the workings of his heart toward God. Those that truly repent of their sins, will not be ashamed to own their repentance. Also, he instructs others what to do, and what to say. David had not only done much, but suffered much in the cause of God; yet he flees to God's infinite mercy, and depends upon that alone for pardon and peace. He begs the pardon of sin. The blood of Christ, sprinkled upon the conscience, blots out the transgression, and, having reconciled us to God, reconciles us to ourselves. The believer longs to have the whole debt of his sins blotted out, and every stain cleansed; he would be thoroughly washed from all his sins; but the hypocrite always has some secret reserve, and would have some favorite lust spared. David had such a deep sense of his sin, that he was continually thinking of it, with sorrow and shame. His sin was committed against God, whose truth we deny by wilful sin; with him we deal deceitfully. And the truly penitent will ever trace back the streams of actual sin to the fountain of original depravity. He confesses his original corruption. This is that foolishness which is bound in the heart of a child, that proneness to evil, and that backwardness to good, which is the burden of the regenerate, and the ruin of the unregenerate. He is encouraged, in his repentance, to hope that God would graciously accept him. Thou desirest truth in the inward part; to this God looks, in a returning sinner. Where there is truth, God will give wisdom. Those who sincerely endeavour to do their duty shall be taught their duty; but they will expect good only from Divine grace overcoming their corrupt nature.