Sometimes we are bogged down with guilt for past sins, and it can be really hard to forgive yourself, and move on.
But God has forgiven our sins, and doesn't remember them anymore.
So, God says, why are you then still holding onto sin that has already been forgiven? Do you not believe that My Son died for your sins? Did Jesus shed His precious blood for nothing?
Think about that for a while. Do you believe that your sins are truly forgiven?
The apostle Paul knew a lot about guilt. After all, he persecuted the church, and probably had blood on his hands.
Twenty years after his conversion he writes:
Brethren, I count not myself to have apprehended: but this one thing I do, forgetting those things which are behind, and reaching forth unto those things which are before, I press toward the mark for the prize of the high calling of God in Christ Jesus.
- Philippians 3:13-14 (KJV)
Although the Bible doesn't specifically say "forgive yourself", it does say to forget the past, and move on. God can not use you, if you dwell in guilt every day.
The Bible clearly says "To love your neighbor as thyself". If you look in the mirror, can you truly say "I love you" to yourself?
Can you see yourself as God sees you?
We cannot change the past.
All we can do is move on, and make up for it.
Check out this article for more about forgiving yourself.