When Jesus died on the cross for us, all our sins were nailed on the cross with Him. Jesus took man's place to save him in order to restore the relationship with God the Father. His blood was shed to wash us clean from our sins.
It is our choice to choose between right and wrong, being obedient or being disobedient to the guidelines of His Word, to sin or not to sin, etc. He gave us the freedom of choice but with that the responsibility to make the correct choice or to live with the consequences of our bad choices. God tells us in His Word that we are a new creature when we are born in the Spirit and this happens only through believing in Jesus Christ. However this "rebirth" is not out of blood, nor the will of man or the will of the flesh. You are seen for who you are now (today), not what you did or who you were. Jesus wants to set you free from your past, all you have to do is to repent your sins before Him. Remember He didn't come for the righteous but for those who have not received Him as their Lord and Saviour, you are precious to Him.
Gal. 5:1: "It was for freedom that Christ set us free"