Recently, while reading in Leviticus 14, I came across this prescription in God’s requirements for the cleansing of people afflicted with leprosy (Note: In Old Testament usage, “leprosy” is a broad term that covers a multiplicity of skin ailments): “Then, if the case of leprous disease is healed in the leprous person, the priest shall command them to take for him who is to be cleansed two live clean birds and the cedarwood and scarlet yarn and hyssop. And the priest shall command them to kill one of the birds in an earthenware vessel over fresh water. He shall take the live bird with the cedarwood and the scarlet yarn and the hyssop, and dip them and the live bird in the blood of the bird that was killed over the fresh water. And he shall sprinkle it seven times on him who is to be cleansed of the leprous disease. Then he shall pronounce him clean and shall let the living bird go into the open field.” (Leviticus 14:3b-7).

Now, obviously there’s much to consider in these verses – ritually, culturally, theologically. But, what struck me most in the moment is the text’s mention of hyssop. Hyssop, in the context of ancient Israel, was probably a particular plant that grew on walls (this from A Concise Hebrew and Aramaic Lexicon of the Old Testament and A Dictionary of Biblical Languages: Hebrew – Old Testament; see also 1 Kings 4:33). David, in his devastating and amazing song of repentance (Psalm 51) says this to the Lord: “Purge me with hyssop, and I shall be clean; wash me, and I shall be whiter than snow” (Psalm 51:7). Why did David reference hyssop? Because he knew God’s Law and God’s Word. He knew the connection between hyssop and a restoration to purity in the sight of God. I think David thought of his sin as something like leprosy – a defiling affliction that made him utterly unclean and unfit to enter God’s presence (Note: Lepers were not permitted to remain within the congregation of Israel but had to live apart from the main camp. It’s also worth observing that washings were part of the restoration process connected with leprosy – wash me, and I shall be whiter than snow). When he prayed a prayer of repentance for restoration, David prayed along the lines of God’s revealed Word in his Law. He prayed like a leper needing cleansing.
Something else strikes me about David’s prayer, especially when I think about it in connection with leprosy. Leprosy is a skin disease. It is, in a sense, surface-deep. And yet, even in the Old Testament Levitical code we get the sense that, symbolically at least, leprosy pointed beneath the skin to deeper issues of sin and brokenness (Note: This does not mean that all lepers were “sinners” any more than every Israelite was a “sinner”). For instance, diagnosing a true case of leprosy involved the priest determining that what appeared on the surface of the body derived from a condition deeper than the skin itself (see Leviticus 13:3). Even this nuance is not lost on the leprous David. His sin is not merely “surface-deep”: “Create in me a clean heart, O God, and renew a right spiritwithin me” (Psalm 51:10). What appeared on the skin of David’s life (adultery and murder) reflected the disease of his heart. It was a disease that only God could heal!
Finally, one last point from David’s song of repentance and its mention of hyssop. There is one other Old Testament reference to the plant, a reference David must also have known about. It’s the reference of Exodus 12:21b-22. As God prepared to bring the judgment of death on the land of Egypt, he determined to rescue his people from his own wrath. This rescue necessitated the blood of a lamb applied to the lintels of the doors of the Israelite’s houses. How was this supposed be done? Just consider Moses’ words in Exodus: “Go and select lambs for yourselves according to your clans, and kill the Passover lamb. Take a bunch of hyssop and dip it in the blood that is in the basin, and touch the lintel and the two doorposts with the blood that is in the basin.” The blood of the Passover lamb applied to the doorway with hyssop covered the Israelites in the day of God’s wrath. As David prays for purging with hyssop, it is that God-ordained covering for sin that he so earnestly desires in his own case.
I want to end with two concluding thoughts, beginning first with the dual nature of repentance that we see in David’s reference to hyssop. True repentance knows and readily admits at least something of the real nature of sin; it’s depth, it’s defilement; it’s ugliness. Sin is like leprosy that springs from the heart, and true repentance says as much. But, even as it readily admits the leprous nature of sin, true repentance also finds real hope in confession. The same mention of hyssop that links Psalm 51 to leprosy also links it to God’s great act of covering and deliverance in Exodus, an act that clearly foreshadows Jesus himself. True repentance is never despairing, it is always the starting point of saving hope.
Second, and finally, when God brings us to a place of utter conviction, what do we do, what do we say? When confession and repentance begin to grab hold of our consciousness, how do we express to God and others the workings of our heart? For David, the answer was God’s Word. In the moment of soul-rending conviction, David’s language cues us to the workings of his mind, the pondering of his heart. In that moment of crisis, David’s mind and heart dove into God’s Law. That Law shaped his song, his prayer of repentance, even down to the very words and images he employed. What better place to go, especially when God’s Word brought not only righteous conviction, but also a pointer to glorious redemption? When the Lord brings us, like David, to such moments, shouldn’t we go to the same refuge this king found so ready and powerful?
All that…from one little plant…Merry Christmas!