For if they do these things in a green tree, what shall be done in the dry? Bleek and others interpret this saying here thus: The green wood represents Jesus condemned to crucifixion as a traitor in spite of his unvarying loyalty to Rome and all lawful Gentile power.
The dry wood pictures the Jews, who, ever disloyal to Rome and all Genesis tile authority, will bring on themselves with much stronger reason the terrible vengeance of the great conquering empire. Theophylact, however, better explains the saying in his paraphrase, "If they do these things in me, fruitful, always green, undying through the Divinity, what will they do to you, fruitless, and deprived of all life-giving righteousness?"
So Farrar, who well summarizes, "If they act thus to me, the Innocent and the Holy, what shall be the fate of these, the guilty and false?"