God created humans as perfect beings. Through an act of disobedience toward God, sin entered the human race and has infected every human being ever since. The Bible declares that the wages of sin is death (Romans 6:23). That means not only physical death but also spiritual death and eternal separation from God, which has dire consequences.
God could have left us that way and forgotten about us, but we are told that God’s great love caused Him to reach out and make a way for humans to come back into a relationship with Him. But sin, our breaking of God’s laws, had to be paid for, and no human effort or sacrifice was good enough to do that. So God took the initiative and sent his Son into the world to pay the penalty for all our sin.
Because Jesus did that-through his death on the cross-the offense of sin has been removed and we are now free to come into a personal relationship with God through faith in Jesus Christ. When we do that we receive eternal life.