The notion often prevails that if there be in the heart this divine witness of God's Spirit, it must needs be perfect, clearly indicating its origin by an exemption from all that besets ordinary human feelings, that it must be a strong, uniform, never flickering, never darkening, and perpetual light, a kind of vestal fire burning always on the altar of the heart! The passage before us, and all others that speak about the matter, give us the directly opposite notion. The Divine Spirit, when it enters into the narrow room of the human spirit, condescends to submit itself, not wholly, but to such an extent as practically for our present purpose is wholly to submit itself to the ordinary laws and conditions and contingencies which befall and regulate our own human nature. Christ came into the world divine: He was found in fashion as a man,' in form a servant; the humanity that He wore limited (if you like), regulated, modified, the manifestation of the divinity that dwelt in it. And not otherwise is the operation of God's Holy Spirit when it comes to dwell in a human heart. There too, working through man, it is found in fashion as a man'; and though the origin of the conviction be of God, and though the voice in my heart be not only my voice, but God's voice there, it will obey those same laws which make human thoughts and emotions vary, and fluctuate, flicker and flame up again, burn bright and burn low, according to a thousand circumstances. The witness of the Spirit, if it were yonder in heaven, would shine like a perpetual star; the witness of the Spirit, here in the heart on earth, burns like a flickering flame, never to be extinguished, but still not always bright, wanting to be trimmed, and needing to be guarded from rude blasts. Else, brother, what does an Apostle mean when he says to you and me, Quench not the Spirit'? what does he mean when he says to us, Grieve not the Spirit'? What does the whole teaching which enjoins on us, Let your loins be girded about, and your lights burning,' and What I say to you, I say to all, Watch!' mean, unless it means this, that God-given as (God be thanked!) that conviction of Fatherhood is, it is not given in such a way as that, irrespective of our carefulness, irrespective of our watching, it shall burn on--the same and unchangeable? The Spirit's witness comes from God, therefore it is veracious, divine, omnipotent; but the Spirit's witness from God is in man, therefore it may be wrongly read, it may be checked, it may for a time be kept down, and prevented from showing itself to be what it is.
And the practical conclusion that comes from all this, is just the simple advice to you all: Do not wonder, in the first place, if that evidence of which we speak, vary and change in its clearness and force in your own hearts. The flesh lusteth against the spirit, and the spirit against the flesh.' Do not think that it cannot be genuine, because it is changeful. There is a sun in the heavens, but there are heavenly lights too that wax and wane; they are lights, they are in the heavens though they change. You have no reason, Christian man, to be discouraged, cast down, still less despondent, because you find that the witness of the Spirit changes and varies in your heart. Do not despond because it does; watch it, and guard it, lest it do; live in the contemplation of the Person and the fact that calls it forth, that it may not. You will never brighten your evidences' by polishing at them. To polish the mirror ever so assiduously does not secure the image of the sun on its surface. The only way to do that is to carry the poor bit of glass out into the sunshine. It will shine then, never fear. It is weary work to labour at self-improvement with the hope of drawing from our own characters evidences that we are the sons of God. To have the heart filled with the light of Christ's love to us is the only way to have the whole being full of light. If you would have clear and irrefragable, for a perpetual joy, a glory and a defence, the unwavering confidence, I am Thy child,' go to God's throne, and lie down at the foot of it, and let the first thought be, My Father in heaven,' and that will brighten, that will stablish, that will make omnipotent in your life the witness of the Spirit that you are the child of God.
