If you keep tropical fish every now and again you need to clean the water. You have to siphon off about a third of the tank because the waste products from the fish make the water toxic which, if left untreated, become deadly. – That’s a picture of what sin is like. – The water in the fish tank has to be replenished with fresh clean water. It seems to me this is a bit like what happens when we confess our sins. We are never purely holy, not 100%, and our sin is like toxic waste. But when we confess our sin and we receive God’s forgiveness, we are replenished and filled afresh with God’s grace, forgiveness and love.