Why do want anyone to believe just like that. When i say um not Christian, I need logical answers because i believe God created logic.
It's logical that God created Adam and Eve, and they were perfect. Without sin, but with a mind of their own, and freewill, and they chose to disobey God. They had 1 rule, and they couldn't obey that rule. That resulted in sin entering the world, the perfect world was not perfect anymore. Death entered the world.
As the world aged, sin multiplied, for sin is like a virus, that consumes all it touches, not just people, but the world itself. Animals started fighting and killing each other, men started eating meat just as animals would eat meat, and sin multiplied.
As time went by, sin made people live shorter life spans, as we got further separation from God, veiled by sin, we lived a far number of years less. And we made more things in sin, to separate us from God.
God sent His Son, as a chance at redemption, to the perfect beings He had created. A chance to once again be made perfect. His Son willingly laid down His own life, for there was no man that could have killed Him, no country could have stood against Him, yet, He gave up his own life, and suffered and was humiliated, just to give us a chance to be made perfect again.
Blood is holy to God, and He knew that only through blood sacrifice could sin be separated from man. So He sent the perfect sacrifice, and to honor His Father, and because of His love for us, Jesus became that perfect sacrifice.
As a result of His sacrifice, God was true to His word, and resurrected His Son, and gave power to all people, to call upon His Son for their own salvation, and separation from sin.
If you accept that Jesus was God's ultimate redemption, and ask His blood to clean yourself, then God will never see your sin again, He will only see the blood of His perfect sacrifice, the blood of His Son.