David wrote Psalm 51 in response to the Lord sending the prophet Nathan to confront his sin (cf. 2 Samuel 12). But it’s inclusion in the canon of scripture bespeaks God’s desire to communicate the nature of the truly penitent to all humanity because all mankind sins and is in need of repentance. David does not focus on sinful actions as the source of his problem, rather his focus is on his sinful heart. Thus, the posture of the penitent and true worshipers is threefold, (1) an intense yearning for God’s presence (vv. 8-9,11); (2) a morally pure life (vv. 6,10,12); and (3) a credible witness to the unfaithful (v.13).
In verse 7, David’s plea is to be purged with hyssop. Hyssop was a plant with hair-like branches and leaves used to sprinkle the blood of the sacrifice for ceremonial cleansing. There was no cleaning agent in the hyssop plant, it was merely an applicator used to sprinkle the blood (cf. Leviticus 14:6). Under the law almost everything was purified with blood, and without the shedding of blood there is no forgiveness of sin (Hebrews 9:22). David’s plea, in essence, was to apply the blood of the sacrifice to cleanse his heart in preparation for life-changing leadership and worship.
Sin is a weight that humanity was not designed to bare. It suppresses the joy and silences the gladness humanity was created to perpetually experience in the presence of God. After Nathan exposed his sin David found words to articulate the magnitude of it’s crushing weight. In verse 8 he says, “the bones that you have broken may rejoice.” The weight of his sin was so heavy that it threatened to crush his bones. Jesus used a similar metaphor when He referred to Himself as the stone (cf. Matthew 21:44), those who fall on Him are broken, but those He falls on (in judgement) are crushed. David was broken by sin but recovered through repentance.
When God is said to hide His face from someone He is said to no longer regard that person favorably. God’s Holy Spirit empowered King Saul for service to reign over Israel. When Saul lost the kingdom it was the Spirit that God removed from him (cf. 1Samuel 16:13-14). David understood that God records all of humanity’s deeds. Unless his sinful deeds were deleted from God’s records David stood no chance to access divine favor and he would thus be rendered useless in God’s service as King of Israel, just as Saul had been. God’s Spirit was essential in executing the kingly responsibilities because David was not just calłed to rule; he was also called to shepherd God’s people.
Whether a person is inherently good or evil is not determined by his or her actions. Actions are merely symptomatic of the condition of one’s heart. The Bible’s prescription for good actions is to “keep your heart with all vigilance, for from it flow the springs of life” (Proverbs 4:23). Jesus taught this concept when he thus spoke, “The good person out of the good treasure of his heart produces good, and the evil person out of his evil treasure produces evil, for out of the abundance of the heart his mouth speaks” (Luke 6:45). Again He said that defilement proceeds from an evil heart, when He said: “…what comes out of the mouth proceeds from the heart, and this defiles a person. For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander” (Matthew 15:18-19). King David was on target when he wrote Psalm 51, for although it was written from his intense desire to be cleansed from personal sin (adultery and conspiracy to commit murder), it was written for the entire congregation in preparation for worship.
Every person has committed sin worthy of judgment. The whole tenor of this psalm is that, if strict justice were God’s only consideration, He would rightfully bring dire judgment on all those who sin. Because God’s motive toward creation is love over justice He sent His Son to extend grace and in mercy withhold that deserved judgment. Faith is the hyssop used to apply His blood that was shed for the forgiveness of sin. His Holy Spirit still empowers us for Godly leadership and service. For that very reason He promises never to withhold His Spirit from His children. But sin still blocks our fellowship with God. The weight of our sins continue to suppresses the joy and silences the gladness we were created to perpetually experience in the presence of God. Therefore, repentance must be a part of our daily lives. It cleanses the heart so that we might live holy (leading morally pure lives), love godly (demonstrating the grace and mercy He first extended to us), and maintain fellowship in His presence by which our credible witness wisely leads the unfaithful to faith in Him. What is the condition of your heart?