When Jesus appeared He declared we needed to be as perfect as His Father in heaven is perfect. In another place, He declared that with men things like that are impossible, but with God all things are possible. Some people think the blood of Christ is some magic robe that if worn correctly hides their sin from God. This makes God as blind as Issac and we are the tricksters getting God to give us a blessing due to another. Nothing could be further from the truth. The power of the blood of Christ is as immeasurable as immediate.
John wrote in 1 John 3:5 "You know that He appeared in order to take away sins". Not hide sins but take them away. In 3:9 he says, "No one who is born of God practices sin, because His seed abides in him; and he cannot sin, because he is born of God." The seed is Christ and Christ does not sin. If we are in Him and He in us, He still does no sin. The good news is we don't have to sin. Sin has no mastery over us. The person of sin (Satan) is left without his keys to his new home.
In short, sin has been abandoned.