Jesus of Nazareth was the Son of God! He proved this by fulfilling ancient prophecies, healing the sick, living the perfect life, but especially by rising from the grave. His death was an atoning sacrifice He made to God, to pay for the sins of all who place their trust in Him.

God is morally perfect, and He requires moral perfection of us all, to be His child and enter Heaven after we die. But no one is perfect -- far from it! Until we become His children, our sins and pride build a wall between us and God.

But Jesus was perfect. He out of love chose to substitute Himself on the cross for sinners. When God raised Christ, on what came to be known as Easter Sunday morning, it showed two facts:

God affirmed Jesus' own sinlessness, and
God accepted Jesus' death on behalf of others. 

Your sins are hanging around your neck like a chain, and they are destroying you. You cannot be justified of sin by keeping the Ten Commandments, going to church, taking the communion, being christened/baptized, going forward to the altar, or following Jesus' moral teachings. Justification of sin is a free gift, which God is happy to give.

You can be justified of your sins by trusting in Jesus identity (that He was the eternal Son of God, come into the world through the virgin Mary), believing in His death and resurrection, and relying on His death and resurrection on your behalf. Then all those other actions (moral obedience, church fellowship, worship) express the renewed person you have become.

Then God in Heaven declares you righteous, and gives you the Spirit of God to change you into a new, free person!