(23) If thou canst believe.--The better MSS. omit the word "believe," and the sentence without it is taken as expressing the sadness of surprise. Our Lord repeats the half-believing, half-despairing words of the father in a tone of sadness, If thou canst. . . . Was this the way in which a man should speak who came to Him as a Healer? Such a one had to learn the great primary lesson that "all things were possible to him that believeth," that the secret of previous failure lay, in part at least, in his own want of faith, as well as in that of the scribes and disciples who had tried their arts of exorcism in vain.

Verses 23, 24. - The most approved reading here is, not Αἴ δύνασαι πιστεῦσαι, but simply Αἴ δύνασαι, So that the English rendering is, If thou canst! All things are possible to him that believeth. Our Lord takes up the father's words. It is as though he said, "Thou sayest to me, 'If thou canst do anything!' Ah, that 'If thou canst!' All things are possible to him that believeth." In other words, our Lord said to him, "Believe in me, and your child shall be healed." It was right that Christ should demand faith in himself; for it was not fitting that he should confer his special benefits on those who disbelieved or doubted about him - that he should thrust his blessings on those who were unworthy of them. The answer of the father is touching and beautiful. Greatly agitated, he cried out and said (we might well suppose (μετὰ δακρύων "with tears," although the weight of evidence is against this addition being retained in the text), I believe; help thou mine unbelief. It is as though he said," I do believe; but my faith is weak. Do thou, therefore, increase and strengthen it; so that whatever there is in me of doubt or remaining unbelief may be taken away, and I may be counted worthy to obtain from thee this blessing for my son." Nor can we doubt that Christ heard a prayer so humble and so fervent, and took away from him the last remains of doubt and unbelief.

9:14-29 The father of the suffering youth reflected on the want of power in the disciples; but Christ will have him reckon the disappointment to the want of faith. Very much is promised to our believing. If thou canst believe, it is possible that thy hard heart may be softened, thy spiritual diseases may be cured; and, weak as thou art, thou mayest be able to hold out to the end. Those that complain of unbelief, must look up to Christ for grace to help them against it, and his grace will be sufficient for them. Whom Christ cures, he cures effectually. But Satan is unwilling to be driven from those that have been long his slaves, and, when he cannot deceive or destroy the sinner, he will cause him all the terror that he can. The disciples must not think to do their work always with the same ease; some services call for more than ordinary pains.Jesus said unto him, if thou canst believe,.... As the man put an "if" on the power of Christ, Christ puts an "if" on the faith of the man; and tacitly suggests, that power was not wanting in himself, but faith in him; and should that cure not be performed, it would not be owing to any inability in him, but to his own incredulity. The Arabic version renders it, "what is this thy: saying, if thou canst do any thing?" What dost thou mean by it? Thou oughtest not to doubt of my power; there is no reason for it, after so many miracles wrought; upbraiding the man with his unbelief; and the Ethiopic version renders it thus, "because thou sayest, if thou canst": wherefore to show that power was not wanting in him, provided he had but faith, it follows,

all things are possible to him that believeth; that is, "to be done" to him, as the Syriac and Ethiopic versions supply: for all things are not possible to be done by the believer himself, but all things are possible to be done for him, by God, or Christ, or the Spirit of God: thus our Lord, as he elsewhere does, ascribes that to faith, which is done by a divine power.