How do we know a power? By thrilling beneath its force. How are we to know the greatness of the power but because it comes surging and rejoicing into our aching emptiness, and lifts us buoyant above our temptations and weakness? Paul was not asking for these people theological conceptions. He was asking that their spirits might be so saturated with and immersed in that great ocean of force that pours from God as that they should never, henceforth, be able to doubt the greatness of that power which wrought in them. The knowledge that comes from experience is the knowledge that we all ought to seek. It is not merely to be desired that we should have right and just conceptions, but that we should have the vital knowledge which is, and which comes from, life eternal.
And that power, which thus we may all know by feeling it working upon ourselves, though it be immeasurable, has its measure; though it be, in its depth and fulness, unknowable and inexhaustible, may yet be really and truly known. You do not need a thunderstorm to experience the electric shock; a battery that you can carry in your pocket will do that for you. You do not need to have traversed all the length and breadth and depth and height of some newly-discovered country to be sure of its existence, and to have a real, though it may be a vague, conception of the magnitude of its shores. And so, really, though boundedly, we have the knowledge of God, and can rely upon it as valid, though partial; and similarly, by experience we have such a certified acquaintance with Him and His power as needs no enlargement to be trusted, and to become the source of blessings untold. We may see but a strip of the sky through the narrow chinks of our prison windows, and many a grating may further intercept the view, and much dust that might be cleared away may dim the glass but yet it _is_ the sky that we see, and we can think of the great horizon circling round and round, and of the infinite depths above there, which neither eye nor thought can travel unwearied. Though all that we see be but an inch in breadth and a foot or two in height, yet we do see. We know the unknowable power that passeth knowledge.
And let me remind you of how large importance this knowledge of and constant reference to the measureless power manifested in Christ is for us. I believe there can be no vigorous, happy Christian life without it. It is our only refuge from pessimism and despair for the world. The old psalm said, 'Thou hast crowned Him with glory and honour, and hast given Him dominion over the works of Thy hands,' and hundreds of years afterwards the writer of the Epistle to the Hebrews commented on it thus, 'We see not yet all things put under Him.' Was the old vision a dream, was it never intended to be fulfilled? Apparently so, if we take the history of the past into account, and the centuries that have passed since have done nothing to make it more probable, apart from Jesus Christ, that man will rise to the height which the Psalmist dreamed of. When we look at the exploded Utopias that fill the past; when we think of the strange and apparently fatal necessity by which evil is developed from every stage of what men call progress, and how improvement is perverted, almost as soon as effected, into another fortress of weakness and misery; when we look on the world as it is to-day, I know not whence a man is to draw bright hopes, or what is to deliver him from pessimism as his last word about himself and his fellows, except the 'working of the strength of the might which He wrought in Christ.' 'We see not yet all things put under Him'--be it so, 'but we see Jesus,' and, looking to Him, hope is possible, reasonable, and imperative.