Doesn't the prophecy reveal very clearly that the purpose of Jesus's death was to redeem the human beings and also enable them to go to Heaven.
Jesus did not die on the Cross to give us forgiveness. Forgiving is one of the hallmarks of the Gospel and Jesus had the power to forgive sins even earlier during His earthly ministry. Didn't Jesus say to some people, “Your sins are forgiven.” Didn't
He command His disciples to forgive even seven times seven? Jesus didn't have to die to assume the power of forgiving.
There could be a second reason for this sacrifice on the Cross.
Though Jesus died on the cross as atonement, God continues to view us as "sinners". Which indeed we are. Heaven being a holy place, a "sinner" cannot step in there. That's His law. God is Holy [I Peter 1:15,16] and the angels are holy too and eternal [Mt 25:31, Lk 20:36] Therefore, anyone entering Heaven has to be totally holy like probably Adam and Eve were before the Fall. [Incidentally, Adam and Eve were able to see God and interact with Him because they were holy. They were the only two human beings who had seen God. After the Fall, God had withdrawn Himself physically from any human being because of their "unholiness".]
Can a human being make himself or herself 100% holy with their own effort? It is impossible. Holiness being an essential condition to step into Heaven, God had to do something again about it. [Read Jn 3: 16 once again]. Man's holiness, lost in garden of Eden, is restored by Jesus's death on the cross. His blood alone will give us this 100 percent holiness. To achieve this, all we are required to do is, “to have faith in Lord Jesus Christ and accept Him as the Saviour or Salvation giver.” So, Jesus shed His blood on the Cross to make a sinner fully holy. [I Jn 1: 7,9]
When Jesus was born the angels announced, “Good news to all people.” What's the import of this Good news? The Good News has 3 elements - (1) the death punishment on human race had been removed/condoned (ii) the doors to Heaven have been thrown open from then (iii) Jesus had come with a different plan for the human beings to step into Heaven, a guaranteed one, as it were.
God wants every man and woman to come and live with Him. Though we have drifted away, God doesn't want even a single human being to go into Satan's camp which is hell.
This is the message of the Cross and “Christ crucified”. Jesus is the Way and the Life. The Death on the cross had made both these possible. Since God had gone absolutely out of His way to rescue us anyhow from eternal death and given a simple formula to reach Him to enjoy eternal life, wouldn't be foolhardy to reject this great Gift? The choice is yours !