Now, brethren, this is Christ's estimate of Himself. I dwell not on it for the purpose of seeking to exhaust its depth of significance. In it there lies the assertion that He, and He only, is the source of all valid knowledge of the deepest sort concerning God and men, and their mutual relations. In it lie the assertion that He, and He only, is the source of all true gladness that may blend with our else darkened lives, and the further assertion that from Him, and from Him alone, can flow to us the purity that shall make us pure. We have to turn to that Man close by His Cross, on whom while He spoke the penumbra of the eclipse of death was beginning to show itself, and to say to Him what the Psalmist said of old to the Jehovah whom he knew, and whom we recognise as indwelling in Jesus: 'With Thee is the fountain of life. Thou makest us to drink of the river of Thy pleasures. In Thy light shall we see light.'
So Christ thought of Himself; so Christ would have as to think of Him. And it becomes a question for us how, if we refuse to accept that claim of a solitary, underived, eternal, and universal power of illuminating mankind, we can save His character for the veneration of the world. We cannot go picking and choosing amongst the Master's words, and say 'This is historical, and that mythical.' We cannot select some of them, and leave others on one side. You must take the whole Christ if you take any Christ. And the whole Christ is He who, within sight of Calvary, and in the face of all but universal rejection, lifted up His voice, and, as His valediction to the world, declared, 'I am the Light of the world.' So He says to us. Oh that we all might cast ourselves before Him, with the cry, 'Lighten our darkness, O Lord, we beseech Thee!'
II. Secondly, we have here a double exhortation.
'Walk in the light; believe in the light.' These two sum up all our duties; or rather, unveil for us the whole fullness of the possible privileges and blessings of which our relation to that light is capable. It is obvious that the latter of them is the deeper in idea, and the prior in order of sequence. There must be the 'belief' in the light before there is the 'walk' in the light. Walking includes the ideas of external activity and of progress. And so, putting these two exhortations together, we get the whole of Christianity considered as subjective. 'Believe in the light; trust in the light,' and then 'walk' in it. A word, then, about each of these branches of this double exhortation.
'Trust in the light.' The figure seems to be dropped at first sight; for it wants little faith to believe in the sunshine at midday; and when the light is pouring out, how can a man but see it? But the apparent incongruity of the metaphor points to something very deep in regard to the spiritual side. We cannot but believe in the light that meets the eye when it meets it, but it is possible for a man to blind himself to the shining of this light. Therefore the exhortation is needed—'Believe in the light,' for only by believing it can you see it. Just as the eye is the organ of sight, just as its nerves are sensitive to the mysterious finger of the beam, just as on its mirroring surface impinges the gentle but mighty force that has winged its way across all the space between us and the sun, and yet falls without hurting, so faith, the 'inward eye which makes the bliss' of the solitary soul, is the one organ by which you and I can see the light. 'Seeing is believing,' says the old proverb. That is true in regard to the physical. Believing is seeing, is much rather the way to put it in regard to the spiritual and divine.