Blood stains. No cleaning product advertises that it contains blood. Yet Christians sing of being washed in Jesus’ blood.
There is a fountain filled with blood,
Drawn from Immanuel’s veins
And sinners plunged beneath that flood
Lose all their guilty stains. — William Cowper
Now there’s a truly unpleasant image. Hardly anything makes me want to wash my hands faster than handling raw meat and getting the blood on them. If sinners are plunged into a fountain of blood, it might cleanse their guilt, but they’ll never get their clothes clean!
To understand the imagery of being washed in the blood of Jesus, we need to consider both the connection between blood and cleansing in the Bible and the role of blood in our own bodies.
Blood and cleansing in the Bible
The book of Leviticus begins by describing the different kinds of blood sacrifices the priests offered at the tabernacle (and later, the temple). The link between blood and cleansing becomes most explicit in instructions for pronouncing a person cleansed from leprosy:
Then the priest is to take one of the male lambs and offer it as a guilt offering,along with the log of oil; he shall wave them before the Lord as a wave offering. He is to slaughter the lamb in the sanctuary area where the sin offering and the burnt offering are slaughtered. Like the sin offering, the guilt offering belongs to the priest; it is most holy. The priest is to take some of the blood of the guilt offering and put it on the lobe of the right ear of the one to be cleansed, on the thumb of their right hand and on the big toe of their right foot. – Leviticus 14:12-14 NIV
Notice that the offering cleanses the person. The application of some of the blood to the person’s body is required for the ritual, but it does not cleanse the person.
All those blood sacrifices require the blood to be splashed on the side of the altar. In sanctifying the tabernacle, Moses sprinkled blood on the tabernacle, the scroll of the law, and all the people.
The writer of Hebrews describes how Jesus initiated a new blood covenant:
But when Christ came as high priest of the good things that are now already here, he went through the greater and more perfect tabernacle that is not made with human hands, that is to say, is not a part of this creation.
He did not enter by means of the blood of goats and calves; but he entered the Most Holy Place once for all by his own blood, thus obtaining eternal redemption. The blood of goats and bulls and the ashes of a heifer sprinkled on those who are ceremonially unclean sanctify them so that they are outwardly clean.
How much more, then, will the blood of Christ, who through the eternal Spirit offered himself unblemished to God, cleanse our consciences from acts that lead to death, so that we may serve the living God! – Hebrews 9:12-14
So Jesus’ literal physical blood has no ritualistic significance, but it cleanses from sin better than the blood of all those animals.
If there’s anything more disgusting than the idea of being washed with blood, it’s drinking it. Yet Jesus said, “Very truly I tell you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you” (John 6:53). And on the night that he was betrayed, he took a cup of wine and declared it his blood.
The function of blood in the body
Whatever we eat or drink goes through our digestive system. From there, our blood carries the nourishment to every cell in our body. Then the blood returns to the heart. On the way, it picks up toxins from every cell in our body and drops them off at the kidneys. That is, blood both nourishes and cleanses.
In other words, the flow of blood is much more like a stream than a fountain. And it remains within the body.
The church is the body of Christ. We as individuals are each like a cell in that body. The blood of Christ acts in his body the same way it does in ours. It nourishes and cleanses it. By whatever means—sacraments, Scripture, personal and corporate worship, Christian fellowship, etc.—it brings us nourishment and cleanses us from sin.
Aren’t you glad your blood cleanses you from the inside and you don’t need to take a bath in it? Aren’t you glad the blood of Jesus cleanses you as a cell in his body even more thoroughly?