1John Chapter 1 verse 7.
Only the Blood of Jesus Purifies us from sin.
(The Bible tells us this.)
This is true, remember Jesus died on the cross for us as a sacrifice for our sin. We were born as sinful, into a sinful world. When we accept Jesus into our hearts we are washed clean of sin by His Blood.We are then new creatures, we are Born Again of the Spirit. Then although tempted we need never sin, it does not have to have dominion over us.