God undermines the arrogant ignorance of man.  God does not desire His servants at their best with hearts and minds filled with strength and skill.  No, it is the broken heart that God accepts as His fragrant sacrifice.  He exalts the humble and humbles the proud.  Men desire full hearts, but God requires emptiness.  He who inhales his own air will asphyxiate.  God alone can administer the breath of life. 

There are some passages in the Scriptures that demand special solemnity. The confession of David in Psalm 51 is so deeply personal that reading it can feel like eavesdropping. One must either join in contrition or stop reading. The weightiness of David’s confession is partly due to the egregiousness of the sin and partly due to the position of the sinner. Not only was the affair with Bathsheba and the murder of Uriah a grotesque abuse of power, but David was God’s anointed king over His people! He was supposed to be a man “after God’s own heart.” It is tragic to see one fall from such heights to such depths. This passage provides a unique look behind the curtain into the broken heart of mighty David, king, a man of God, conqueror, psalmist, adulterer, murderer.
Commentators tread lightly around Psalm 51 to maintain reverence. This was true of Spurgeon, a great pontificator of the Scriptures. See here his thoughts on the Psalm:
I postponed expounding it week after week, feeling more and more my inability for the work.  Often I sat down to it, and rose up again without having penned a line.  It is a bush burning with fire yet not consumed, and out of it a voice seemed to cry to me, “Draw not nigh hither, put off thy shoes from off thy feet.”  The Psalm is very human, its cries and sobs are of the one born of woman; but it is freighted with an inspiration all divine, as if the Great Father were putting words into his child’s mouth.  Such a Psalm may be wept over, absorbed into the soul, and exhaled again in devotion; but, commented on—ah! Where is he who having attempted it can do other than blush at his defeat? [2]
Spurgeon’s humility is, of course, appropriate.  Nevertheless, this passage is ripe with lessons—particularly about repentance.  This article, guided by Psalm 51 and drawing from Spurgeon’s own thoughts, will briefly consider the nature and necessity of Christian repentance and the kindness of God that makes it possible.
The Nature of Repentance – “Sweet Sorrow”
Few confessions express contrition as candidly as David’s in this Psalm.  For many, the fear of consequences poses as pious regret—a particularly cunning wolf in sheep’s clothing.  The despair may be genuine, but the source is all too human.  Often it is only after being caught that the smirk falls from our faces.  It is easy to underestimate man’s proclivity for self-deception.  David only beheld his wickedness after the prophet Nathan spat in his blind eyes.  The truly repentant heart is broken, there is no room for self-preservation.  Indeed, “the sacrifices of God are a broken spirit; a broken and contrite heart, O God, you will not despise.”[3]
Though it is fitting to feel brokenness over our sin, we do not grieve as those who do not have hope.  It is not for the strange pleasure of self-abasement that we reject our sinful tendencies.  We repent toward restoration.  We sorrow in sin so that we may rejoice in righteousness. Because Christ suffered for sinners, our repentance is an act of faith in the power of God to make us whole again.  Praise be to God who will not despise our contrition but lifts those who fall before Him.[4]
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