I take issue with the statement that Christ had to suffer death or He could not Reign as King.
Christ was already King. He was perfect and therefore did not need to suffer any punishment to earn a reward that His Father promised Him, that is all that His Father had.
He died on the cross very early in the process, people can survive on the cross several days. The other two that hung on the cross were very much still alive when their legs were broken so that they could not stand and therefore would be unable to breath. Christ was already dead because He gave up The Ghost. He had power over life and death and used that power to die.
We are not perfect. The punishment for sin is death. Christ suffered our punishment for us if we accept Him. By our accepting the punishment given freely by Him we may live again with God because our sin is covered, hidden in the blood of Christ because the debt of our sin is paid. It was paid by someone who did not owe it and paid it anyway.
I don’t think most people have a clue what all that means, about how Christ can somehow take upon Himself my pains and agony and suffer for them in the past even before I had them. How he can be punished for my sins even before I commit them. His punishment had to be unbelievably horrible to cover not just my sin but every bodies sins.
He did not have to do it. The Lord said that “greater love have no man but that he lay down his life for another”. He did that but multiplied by billions.
The purpose in Christ coming was foretold by the holy prophets. And as it was foretold "A bone of Him shall not be broken", Exodus 12:46 and Numbers 9:12. Christ was the final perfect required 'blood' sacrifice of all time.. The Passover lamb. The crucifixion was not required for Christ to gain, He in the flesh was God with us.. But, the devil and a numbered of his fallen angels have already been judged to death. God created these entities in love, but they rebelled and attempted to replace God and drew from God large numbers of soul/spirit intellects... The devil and those fallen angels will never partake of flesh, they are already judged to death. It is/was a fulfillment of prophecy - similar to a kinsman redeemer .. legal binding contract.
There are still some sins, like premeditate homicide and rape that require a 'face to face' with the Creator to be forgiven... The ONLY thing that changed, fulfilled, was no longer a blood sacrifice required for remission of sin. We can go directly to the Father, in Christ name with a repentant heart/mind to seek forgiveness.
Too many Christians think those Ten Commandments do not apply to them. Well, no Christian worth his/her salt would call themselves Christian if they break any of the Ten. That is what is meant to believe in Christ, by keeping His Commandments.