The experiences of a repentant soul, anticipating the confession of sin by the godly Jewish remnant in the last days, when they humble themselves before God for the rejection and murder of Christ (vs. 14).
Psalms 49 warns us against the worldly man that trusts in his riches. Psalms 50 rebukes the religious man who trusts in the outward forms of religion, such as sacrifices and burnt offerings. Psalms 51 presents the repentant man who, acknowledging that sacrifices and burnt offerings are of no avail (vs. 16), humbles himself before God and looks to the mercy of God for cleansing.
(vv. 1-3) The psalm opens with a repentant man appealing to the grace and loving-kindness of God. He sees that with God there is an “abundance” (JND) of tender mercies, and therefore God’s mercy is greater than his sin. So the prodigal in the parable can say: “How many hired servants of my father’s have bread enough and to spare.”
In the light of the grace of God, the repentant man can acknowledge his transgressions and sin, and look to God to blot out his sins from before God’s face, and cleanse him from the sin that is ever before him.
(vs. 4) However much we may sin against man, all sin is against God. The repentant man has a deep conviction of the true character of sin as against God, and in the sight of God. Sin is a defiance of God, and being so, God will be justified in judging the sinner.
(vv. 5-6) Furthermore, the sin is traced to its origin and found to consist, not simply in sinful acts, but in a sinful nature. Hence the sinner requires not only cleansing from actual sins, but a new nature in “the inward parts.”
(vv. 7-8) Having acknowledged his sin, the repentant man looks to God to cleanse him with hyssop. The reference is to the cleansing of the leper, and those who had defiled themselves by contact with a dead body. The hyssop was dipped in blood, which was then sprinkled on the person to be cleansed. It surely speaks of the righteous ground on which God can cleanse―the precious blood of Christ. Being cleansed, the soul would be restored to joy and gladness.
(vv. 9-13) Furthermore, there is the desire, not only that the repentant sinner may be cleansed, but that God Himself will no longer see his sins, and further, that the cleansing may not only be outward, but inward, so that he may have “a clean heart” and a right spirit. Thus suited for God’s presence, and filled with the Spirit, he would be led again into the joy of salvation. Sustained by a “willing spirit” (JND), in contrast to his past sin in defiance of God, the repentant sinner, now restored, would be able to teach others in the ways of God so that sinners would be turned to God.
(vv. 14-15) Having sought cleansing from his own sins, the psalmist seeks deliverance from the blood-guiltiness of the nation, guilty of the blood of their own Messiah (Matt. 27:2525Then answered all the people, and said, His blood be on us, and on our children. (Matthew 27:25)). Then indeed he would sing of the “righteousness” of God, expressed as we know in the death of Christ. The declaration of the righteousness of God will lead to the praise of the Lord.
(vv. 16-17) The soul, having profited by the witness of God in Psalms 50, now disclaims all confidence in legal sacrifices. It is realized that if the soul looks to the grace of God for cleansing, the only right condition for being cleansed, is “a broken spirit” and “a contrite heart.” Such, God will not despise.
(vv. 18-19) The repentance of the remnant of the Jews, anticipated in the psalm, prepares the way for the restoration of Zion, according to God’s good pleasure. Then, indeed, God will take pleasure in sacrifices offered, not with the legal thought of obtaining blessing, but as the witness of the ground on which the nation is blessed (cf. Ezekiel 43:18, 27; 45:15-2518And he said unto me, Son of man, thus saith the Lord God; These are the ordinances of the altar in the day when they shall make it, to offer burnt offerings thereon, and to sprinkle blood thereon. (Ezekiel 43:18)
27And when these days are expired, it shall be, that upon the eighth day, and so forward, the priests shall make your burnt offerings upon the altar, and your peace offerings; and I will accept you, saith the Lord God. (Ezekiel 43:27)
15And one lamb out of the flock, out of two hundred, out of the fat pastures of Israel; for a meat offering, and for a burnt offering, and for peace offerings, to make reconciliation for them, saith the Lord God. 16All the people of the land shall give this oblation for the prince in Israel. 17And it shall be the prince's part to give burnt offerings, and meat offerings, and drink offerings, in the feasts, and in the new moons, and in the sabbaths, in all solemnities of the house of Israel: he shall prepare the sin offering, and the meat offering, and the burnt offering, and the peace offerings, to make reconciliation for the house of Israel. 18Thus saith the Lord God; In the first month, in the first day of the month, thou shalt take a young bullock without blemish, and cleanse the sanctuary: 19And the priest shall take of the blood of the sin offering, and put it upon the posts of the house, and upon the four corners of the settle of the altar, and upon the posts of the gate of the inner court. 20And so thou shalt do the seventh day of the month for every one that erreth, and for him that is simple: so shall ye reconcile the house. 21In the first month, in the fourteenth day of the month, ye shall have the passover, a feast of seven days; unleavened bread shall be eaten. 22And upon that day shall the prince prepare for himself and for all the people of the land a bullock for a sin offering. 23And seven days of the feast he shall prepare a burnt offering to the Lord, seven bullocks and seven rams without blemish daily the seven days; and a kid of the goats daily for a sin offering. 24And he shall prepare a meat offering of an ephah for a bullock, and an ephah for a ram, and an hin of oil for an ephah. 25In the seventh month, in the fifteenth day of the month, shall he do the like in the feast of the seven days, according to the sin offering, according to the burnt offering, and according to the meat offering, and according to the oil. (Ezekiel 45:15‑25)).