That wide statement is meant, I suppose, for the disciples as well as for the father. 'All things are possible' both in reference to benefits to be received, and in reference to power to be exercised. 'If thou canst believe, poor suppliant father, thou shalt have thy desire. If thou canst believe, poor devil-ridden son, thou shalt be set free. If ye can believe, poor baffled disciples, you will be masters of the powers of evil.'
Do you remember another 'if' with which Christ was once besought? 'There came a leper to Him, beseeching Him, and kneeling down to Him, and saying unto Him, If Thou wilt, Thou canst make me clean.' In some respects that man had advanced beyond the father in our story, for he had no doubt at all about Christ's power, and he spoke to Him as 'Lord.' But he was somehow not quite sure about Christ's heart of pity. On the other hand, the man in our narrative has no doubt about Christ's compassion. He may have seen something of His previous miracles, or there may still have been lying on our Lord's countenance some of the lingering glory of the Transfiguration--as indeed the narrative seems to hint, in its emphatic statement of the astonishment and reverential salutations of the crowd when He approached--or the tenderness of our Lord's listening sympathy may have made him feel sure of His willingness to help. At any rate, the leper's 'if' has answered itself for him. His own lingering doubt, Christ waives aside as settled. His 'if' is answered for ever. So these two 'ifs' in reference to Christ are beyond all controversy; His power is certain, and His love. The third 'if' remains, the one that refers to us--'If thou canst believe'; all hinges on that, for 'all things are possible to him that believeth.'
Here, then, we have our Lord telling us that faith is omnipotent. That is a bold word; He puts no limitations; 'all things are possible.' I think that to get the true force of these words we should put alongside of them the other saying of our Lord's, 'With God all things are possible.' That is the foundation of the grand prerogative in our text. The power of faith is the consequence of the power of God. All things are possible to Him; therefore, all things are possible to me, believing in Him. If we translate that into more abstract words, it just comes to the principle that the power of faith consists in its taking hold of the power of God. It is omnipotent because it knits us to Omnipotence. Faith is nothing in itself, but it is that which attaches us to God, and then His power flows into us. Screw a pipe on to a water main and turn a handle, and out flows the water through the pipe and fills the empty vessel. Faith is as impotent in itself as the hollow water pipe is, only it is the way by which the connection is established between the fulness of God and the emptiness of man. By it divinity flows into humanity, and we have a share even in the divine Omnipotence. 'My strength is made perfect in weakness.' In itself nothing, it yet grasps God, and therefore by it we are strong, because by it we lay hold of His strength. Great and wonderful is the grace thus given to us, poor, struggling, sinful men, that, looking up to the solemn throne, where He sits in His power, we have a right to be sure that a true participation in His greatness is granted to us, if once our hearts are fastened to Him.
And there is nothing arbitrary nor mysterious in this flowing of divine power into our hearts on condition of our faith. It is the condition of possessing Christ, and in Christ, salvation, righteousness, and strength, not by any artificial appointment, but in the very nature of things. There is no other way possible by which God could give men what they receive through their faith, except only their faith.