Hebrews 8:12
For I will be merciful to their unrighteousness, and their sins and their lawless deeds, I will remember no more.

Many of us like to talk about past failures of people we know and rejoice in our perfection without realising that the person we are talking about is loved by God. God loves all people no matter what background they may have or where they may have come from. I can remember the times when my friends said bad things about me. I also know the failures of some of my friends that did annoy me. However, God is not like us and so the way He does things can make us feel it is unjust.
What God thinks of us is the best and we should learn to get hold of it because it is life.

When you become a born again Christian dear friend, man can look at you and remember what you were like in the past. When God looks at you through the new covenant, He declares, “I will be merciful to your unrighteousness, and your sins and lawless deeds I will remember no more.”
God is reassuring us that when we come to Him, we must not think that, He is thinking about our sins. Every time He sees us, He sees Christ and not our sins. He does not have a record nor is mindful of our failures and shortcomings. That’s why He says He does not remember our sins anymore, never again.

God can say that all our sins He remembers no more because there is a time when He remembered them and punished every one of them (our sins) – in the body of His Son at the cross. He punished every single one of them until Jesus cried out, “It is finished!” (John 19:30) That is why today, God can justly say, “Your sins I will remember no more.”

We all know that we sin from time to time. But the good news is that all our sins have already been dealt with at the cross. They have been washed away by the blood of Jesus. Now we can come into God’s presence, He sees us without our sins. So beloved, forget your past failures. Believe that God remembers your sins no more and be the righteous man that you already are in Christ