Short Answer: "Crucifixion," or its equivalent, is INTRINSIC to the kind of love in which God forgave and continues to forgive us, His enemies, who nailed Jesus to a cross." (cf. Rom. 5:6-10; Col. 1:21-22).
This one-sentence answer can be expanded into a short paragraph as follows:
To say that the kind of love which forgives ENEMIES "intrinsically" brings "crucifixion" upon the one who practices it, is to say that it is not something imposed arbitrarily from without, but is an inherent consequence of such love; it is a revelation of how COSTLY such love is to the one who practices it. Thus, Christ did not die so that God could forgive us, but rather God's forgiving love of us is what brought about the death of Christ.
In other words, Christ's death was not the cause of God's forgiveness, but rather its accompaniment.
Christ had to die because we were dead; and we were dead because we were appointed to die; (Heb. 9:27). and we were appointed to die because paradoxically, our ultimate destiny is life and life abundant. The very life of God is to be our life, and only the experience of death can prepare us for this life. The extremity of need, which is death, is the only worthy complement to the bounty of His life. Death is a spiritual vacuum that, when exposed to the life of Christ, whose life is perfect union with God, causes us to fill our lungs like a man underwater who has run out of air and breaks the surface gasping for breath. Death is the compression of the human spirit like the compression of the bulb on a syringe, the result being that when the compression is released, we suck in the water of life. Christ was named Immanuel (God with us) and He joined us in our death that we might join Him in His life. He was subjected to death so that in the flesh, as one of us and as our forerunner, the firstfruits (I Cor. 15:20,23) of all mankind, He would be "raised from the dead by the glory of the Father [so that] we too may live a new life." (Rom. 6:4). The last enemy, Death is defeated by being forced to be an instrument for life, and then it is vanquished forever.
Death is not the result of the abuse of man's free will. God planned for it to be the temporal, all-pervasive condition of humanity to prepare us to experience His life in all its fulness. Nothing but sin and death can bring out the best in God. They bring out a quality of His love which reveals the passion in God to be with us, even though it means he became flesh in order to participate in the slime pits of our human condition. So Jesus, Immanual, joined us and died on the cross bearing spiritually, soulically and physically our sin and all its consequence. Without sin and death, the love of God would be experienced as merely benign, but when that love comes to us bearing our sin and death and all the effects on spirit, soul and body, it is revealed in all its depth, brilliance and fire.
We had to be lured by the temptation to be independently self-sufficient like we were led to believe God was; tempted to be gods who control their own destinies. We didn't know that not even God is self-sufficient in that mode. He is relational by nature. He is the Father/Mother/Son/Daughter God and He draws His sufficiency from His relational being. We have to experience that which is alien to our nature (independence and separation) before we can ever assimilate that which is native to us (dependence and union). This union is to be found in the Spirit of God. (Gal. 2:20). So we say with St. Paul "that I may know Him and the power of His resurrection and the fellowship of His sufferings, being made conformable unto His death, if by any means I might attain unto the resurrection from among the dead." (Phil. 3: 10-11).
The reason Christ had to die was because God is "not willing for ANY to perish, but that all shall come to repentance." (II Pet. 3:9). Thus we know that it is His expressed will, that all be saved. Since Paul said that He works "ALL THINGS after the counsel of His own will," (Eph. 1:11) I think it's safe to say that He knows how to get His will accomplished, and consequently, all will be saved! To say otherwise is to suggest that God isn't powerful enough to cause His will to be done. And by the way, if you're looking for a scripture that promises salvation for everyone, how about Romans 11:26, for starters, where Paul writes, "And so all Israel shall be saved." Even Lot's wife? (Gen. 19:26). Even Nadab and Abihu? (Num.
3:4). Even Hophni and Phinehas? (I Sam. 2:22-25; 4:17). And what about Judas? (Matt. 27:3-8). Nevertheless, it was God, Paul said, who subjected the creation to vanity, (Rom. 8:20) and in fact, he goes farther than that, and says, "For God has consigned ALL MEN to disobedience, that He may HAVE MERCY UPON ALL!" (Romans 11:32). Since God subjected the creation and everything in it to vanity and bondage, He is the only one who can deliver us from that, which is why John the Beloved wrote, "For God so loved THE WORLD that He gave His only begotten Son, that whoever believes in him should not perish, but have eternal life. For God sent the son into the world, not to condemn the world, but that the world might be saved through Him." (Jn. 3:16-17). Jesus said, "And I, if I be lifted up from the earth, will draw ALL MEN unto me." (Jn. 12:32). Was Jesus lying here? Fantasizing?
Optimistically hoping? Or telling the truth? He said of himself that He was the truth, the way and the life, (Jn. 14:6) and the Apostle John said of him, "That (Jesus) was the true Light, which lighteth EVERY MAN that cometh into the world." (Jn. 1:9). This is why Jesus had to die, my friend. His blood paid the price for our release from sin. (Rom. 3:23-25; 5:10; Heb.
9:22; 10:4; I Jn. 2:2). On the cross, He said, "It is finished." (Jn.
19:30). That tells us that He accomplished what He set out to do. And while His sacrificial death bought our freedom from sin, it did much more than that. Paul puts the whole thing in capsule form in Romans 5
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"For if, when we were enemies, we were reconciled to God by the death of his son, much more, being reconciled, we shall be saved by his life." Man could not save himself from the dreadful bondage he found himself in, (Eph. 2:1:
12-19; Col. 2:13-14) and thus, God, who had subjected him to this in order to show His eternal glory to man, sent His only begotten Son to die for us.
That's why Jesus had to die.