Charles H. Spurgeon on Psalms 90:8

It is a well known fact that the appearance of objects, and the ideas which we form of them, are very much affected by the situation in which they are placed in respect to us, and by the light in which they are seen. Objects seen at a distance, for example, appear much smaller than they really are. The same object, viewed through different mediums, will often exhibit different appearances. A lighted candle, or a star, appears bright during the absence of the sun; but when that luminary returns, their brightness is eclipsed. Since the appearance of objects, and the ideas which we form of them, are thus affected by extraneous circumstances, it follows, that no two persons will form precisely the same ideas of any object, unless they view it in the same light, or are placed with respect to it in the same situation.

Apply these remarks to the case before us. The psalmist addressing God, says, Thou hast set our iniquities before thee, our secret sins in the light of thy countenance. That is, our iniquities or open transgressions, and our secret sins, the sins of our hearts, are placed, as it were, full before God's face, immediately under his eye; and he sees them in the pure, clear, all disclosing light of his own holiness and glory. Now if we would see our sins as they appear to him, that is, as they really are, if we would see their number, blackness and criminality, and the malignity and desert of every sin, we must place ourselves, as nearly as is possible, in his situation, and look at sin, as it were, through his eyes. We must place ourselves and our sins in the centre of that circle which is irradiated by the light of his countenance where all his infinite perfections are clearly displayed, where his awful majesty is seen, where his concentrated glories blaze, and burn and dazzle, with insufferable brightness. And in order to this, we must, in thought, leave our dark and sinful world, where God is unseen and almost forgotten, and where consequently, the evil of sinning against him cannot be fully perceived —and mount up to heaven, the peculiar habitation of his holiness and glory, where he does not, as here, conceal himself behind the veil of his works, and of second causes, but shines forth the unveiled God, and is seen as he is.

My hearers, if you are willing to see your sins in their true colours; if you would rightly estimate their number, magnitude and criminality, bring them into the hallowed place, where nothing is seen but the brightness of unsullied purity, and the splendours of uncreated glory; where the sun itself would appear only as a dark spot; and there, in the midst of this circle of seraphic intelligences, with the infinite God pouring all the light of his countenance round you, review your lives, contemplate your offences, and see how they appear. Recollect that the God, in whose presence you are, is the Being who forbids sin, the Being of whose eternal law sin is the transgression, and against whom every sin is committed. —Edward Payson.