Have you ever spilled mustard or ketchup on a clean, white suit or sweater you were wearing? It’s a stain you can’t hide—and it can be embarrassing if you have to stand up and speak in front of people with that fresh stain showing!

King David had a much more serious problem with a stain. The prophet Nathan confronted him about it and told him that it needed to be addressed (2 Samuel 12:1-13). Was there any way to remove the stain of sleeping with another man’s wife and then murdering her husband? Sometimes we think we can cover up the stains of our sins by placing blame elsewhere. But the stains remain.

In Psalm 51, David writes, “Cleanse me with hyssop.” The word for “cleanse” here literally means “un-sin.” Imagine being able to push an “undo” button to wipe out something wrong you have done! Hyssop was a plant with brush-like branches, and in ancient Israel it was used for purification rites. Moses dipped a hyssop branch in blood and used it to sprinkle people and objects to declare them purified (Hebrews 9:19-23). Hyssop was also used to spread blood on the doorframes of Israelites’ houses before they were freed from slavery in Egypt (Exodus 12:21-23).

This pointed to the blood of Jesus, which “purifies us from all sin” (1 John 1:7). As Christians, we know that there is one cleansing agent—the blood of Christ—that can wash away our sins. So if we repent and ask God for forgiveness, we will be cleansed, for Jesus’ sake.