According to 1 John 1:7, what cleanses us from all sin?

Answer: The blood of Jesus

If we walk in the light as He is in the light, we have fellowship with one another, and the blood of Jesus His Son cleanses us from all sin.

“But if we walk in the light as He is in the light, we have fellowship with one another, and the blood of Jesus His Son cleanses us from all sin.”— 1 John 1:7 (BSB)