Our sins are gone. We've been set free.
It's impossible to find a human who has not sinned, for the Bible says we are born in sin. Everyone has faults. We all have bad days, we slip, and mess up. We all have that thing we struggle with, that thing the devil keeps throwing in our faces and taunting us with. Even after we've asked for God's forgiveness, guilt can still hang over our heads and weigh us down. The thing is, though, once sin is under the blood of God, He no longer remembers it. It's gone. So, if God no longer remembers your sin, the devil has no right to keep throwing it in your face like a confetti bomb.
If you were the only one who would receive God into your heart and accept His forgiveness, He still would've died on the cross.
Most of us have been in the same place of believing a sin is too great to be forgiven. Some of us have even gone as far to say, "I'm not worthy enough to ask God to forgive me, so I won't." The devil will try all kinds of lies to keep you from going to your knees and asking God to forgive you, even if you know God loves you and will forgive you. Don't let the devil slip that into your head. Jesus died on the cross just for you. No one will ever be worthy enough. Yet, Christ Jesus loves us despite our faults, and He wants you to come to Him. He wants to come into your life, and if you'll ask, to cover your sins with His blood.
If you feel guilty about a sin, or sins, you've asked God to forgive, it's a sure sign the devil is trying to distract you from what God is trying to do in your life.
Holding onto your past is dangerous. The devil will hold it over your head to keep you from growing closer to God. Accepting God's forgiveness and realizing that your sin can no longer be held over your head, is freeing. Letting go of your past is like dropping a hundred-pound boulder. The devil will remind you of your sin, he'll remind God of your sin, but once it's under the blood, God simply can't see it anymore.
Can you imagine the look on the devil's face when God told him He couldn't remember what it was that Paul had done to His children? It's the same look the devil gets when he asks God about our sin.
Paul of Tarsus persecuted Christians in the name of God. Not only that, but he killed them, zealously, believing he was doing God's work. When God got a hold of him, and changed him, Paul had to accept God's forgiveness for what he'd done. If anyone didn't feel worthy of God's forgiveness, it would've been Paul. God had to remind Paul that His grace was sufficient. Not accepting God's forgiveness would be the equivalent of telling God "You're not powerful not to cover my sins. Your grace isn't sufficient." Sins get nasty, they get ugly, but once you ask God to forgive you, those sins are gone. As Paul had to, accept your forgiveness and let God work through you.
The devil can tell God about your sins 'till he's blue in the face and God still won't be able to remember what He's forgiven.
People will constantly point out your faults and tell you what you've done. The devil will do the same thing. But you've asked God for forgiveness. You've asked God to cover you with His blood. The only opinion that matters about you is God's. If He says you're forgiven, then believe it and praise Him for it. Your sins have been thrown into the sea of forgetfulness, and on judgement day, God still won't remember the sins the devil beats you over the head for.
2 Corinthians 12:8-9a
8. For this thing I besought the Lord thrice, that it might depart from me.
9a. And he said unto me, My grace is sufficient for thee: for my strength is made perfect in weakness.