But there is not only the idea of activity here, there is the further notion of progress. Unless Christian people to their faith add work, and have both their faith and their consequent work in a continual condition of progress and growth, there is little reason to believe that they apprehend the light at all. If you trust the light you will walk in it; and if your days are not in conformity nor in communion with Him, and are not advancing nearer and nearer to the central blaze, then it becomes you to ask yourselves whether you have verily seen at all, or trusted at all, 'the Light of life.'
III. Thirdly, there is here a warning.
'Walk whilst ye have the light, lest the darkness come upon you.' That is the summing up of the whole history of that stiff-necked and marvellous people. For what has all the history of Israel been since that day but groping in the wilderness without any pillar of fire? But there is more than that in it. Christ gives us this one solemn warning of what falls on us if we turn away from Him. Rejected light is the parent of the densest darkness, and the man who, having the light, does not trust it, piles around himself thick clouds of obscurity and gloom, far more doleful and impenetrable than the twilight that glimmers round the men who have never known the daylight of revelation. The history of un-Christian and anti-Christian Christendom is a terrible commentary upon these words of the Master, and the cries that we hear all round us to-day from men who will not follow the light of Christ, and moan or boast that they dwell in agnostic darkness, tell us that, of all the eclipses that can fall upon heart and mind, there is none so dismal or thunderously dark as that of the men who, having seen the light of Christ in the sky, have turned from it and said, 'It is no light, it is only a mock sun.' Brethren, tempt not that fate.
And if Christian men and women do not advance in their knowledge and their conformity, like clouds of darkness will fall upon them. None is so hopeless as the unprogressive Christian, none so far away as those who have been brought nigh and have never come any nigher. If you believe the light, see that you growingly trust and walk in it, else darkness will come upon you, and you will not know whither you go.
IV. And lastly, there is here a hope and a promise.
'That ye may be the sons of light.'
Faith and obedience turn a man into the likeness of that in which he trusts. If we trust Jesus we open our hearts to Him; and if we open our hearts to Him He will come in. If you are in a darkened room, what have you to do in order to have it filled with glad sunshine? Open the shutters and pull up the blinds, and the light will do all the rest. If you trust the light, it will rush in and fill every crevice and cranny of your hearts. Faith and obedience will mould us, by their natural effect, into the resemblance of that on which we lean. As one of the old German mystics said, 'What thou lovest, that thou dost become.' And it is blessedly true. The same principle makes Christians like Christ, and makes idolaters like their gods. 'They that make them are like unto them; so is every one that trusteth in them,' says one of the Psalms. 'They followed after vanity and are become vain,' says the chronicler of Israel's defections. 'We with unveiled faces beholding'—or mirroring—'the glory of the Lord, are changed into the same image.' Trust the light and you become 'sons of the light.'
And so, dear friends, all of us may hope that by degrees, as the reward of faith and of walking, we still may bear the image of the heavenly, even here on earth. While as yet we only believe in the light, we may participate in its transforming power, like some far-off planet on the utmost bounds of some solar system, that receives faint and small supplies of light and warmth, through a thick atmosphere of vapour, and across immeasurable spaces. But we have the assurance that we shall be carried nearer our centre, and then, like the planets that are closer to the sun than our earth is, we shall feel the fuller power of the heat, and be saturated with the glory of the light. 'We shall see Him as He is'; and then we too 'shall blaze forth like the sun in the kingdom of our Father.'
THE LOVE OF THE DEPARTING CHRIST
'… When Jesus knew that His hour was come that He should depart out of this world unto the Father, having loved His own which were in the world, He loved them unto the end.'—JOHN xiii. 1.