It is not His Sermon on the Mount that He would have remembered, but His Cross. There would have been no Gospel had there been no Cross; and the death on the Cross would have been useless for the removal of human guilt, if He had not risen from the dead. He said it behooved Him to suffer because He had to show the evil of sin, and evil is most manifest in the Crucifixion of Goodness. No greater darkness would ever descend upon the earth than that which fell upon Him on Calvary. In all other wars, there is generally a gray, or a mixture of good and evil, on both sides; but in the Crucifixion, there was black on one side and white on the other. Evil would never be stronger than it was on that particular day. For the worst thing that evil can do is not to bomb cities and to kill children and to wage wars; the worst thing that evil can do is to kill Goodness. Having been defeated in that, it could never be victorious again.
Goodness in the face of evil must suffer, for when love meets sin, it will be crucified. A God Who wears His Sacred Heart upon His sleeve, as Our Lord did when He became man, must be prepared to have human daws peck at it. But at the same time, Goodness used that very suffering as a condition of overcoming evil. Goodness took all the anger, wrath, and hate, and pleaded: “Forgive” it took life and offered it for another. Hence to Him it was expedient that He suffer in order to enter glory. Evil, conquered in its full armor and in the moment of its monumental momentum, might in the future win some battles, but it would never win the war.
No hope could be given to a wounded world by a Confucius, Buddha, or even a Christ who taught goodness and then rotted in the grave. No healing can be brought to broken wings by a humanism, which is brotherhood without tears; or by a gentle Christ Who has no source of knowledge distinct from any other teacher, and Who, in the end like them, could not burst the fetters of death, nor prove that truth crushed to earth may rise again. – from Life of Christ (1958)