At the brightness that was before him - From the flash - the play of the lightnings that seemed to go before him.

His thick clouds passed - or, vanished. They seemed to pass away. The light, the flash, the blaze, penetrated those clouds, and seemed to dispel, or to scatter them. The whole heavens were in a blaze, as if there were no clouds, or as if the clouds were all driven away. The reference here is to the appearance when the vivid flashes of lightning seem to penetrate and dispel the clouds, and the heavens seem to be lighted up with a universal flame.

Hail-stones - That is, hailstones followed, or fell.

And coals of fire - There seemed to be coals of fire rolling along the ground, or falling from the sky. In the corresponding place in 2 Samuel 22:13 the expression is, "Through the brightness before him were coals of fire kindled." That is, fires were kindled by the lightning. The expression in the psalm is more terse and compact, but the reason of the change cannot be assigned.

At the brightness that was before him his thick clouds passed - The word נגה nogah signifies the lightning. This goes before him: the flash is seen before the thunder is heard, and before the rain descends; and then the thick cloud passes. Its contents are precipitated on the earth, and the cloud is entirely dissipated.

Hail-stones and coals of fire - This was the storm that followed the flash and the peal; for it is immediately added: -

At the brightness that was before him, The lightning that came out of the thick clouds; which may denote, either the coming of Christ to take vengeance on the Jewish nation, which was swift and sudden, clear and manifest; or the spreading of the Gospel in the Gentile world, in which Christ, the brightness of his Father's glory, appeared to the illumination of many; see Matthew 24:27; and both may be intended, as the effects following show;

his thick clouds passed; that is, passed away; the gross darkness, which had for so many years covered the Gentile world, was removed when God sent forth his light and truth; and multitudes, who were darkness itself, were made light in the Lord;

hail stones and coals of fire; the same Gospel that was enlightening to the Gentiles, and the savour of life unto life unto them, was grievous, like hail stones, and tormenting, scorching, irritating, and provoking, like coals of fire, and the savour of death unto death, to the Jews; when God provoked them, by sending the Gospel among the Gentiles, and calling them: or these may design the heavy, awful, and consuming judgments of God upon them, which are sometimes signified by hail storms; see Revelation 8:7. In 2 Samuel 22:13, it is only, "through the brightness before him were coals of fire kindled".

At the brightness that was before him his thick clouds passed, hail stones and coals of fire.

18:12 At - His glorious and powerful appearance. Passed - Or, passed away, vanished, being dissolved into showers.

12. Out of this obscurity, which impresses the beholder with awe and dread, He reveals Himself by sudden light and the means of His terrible wrath (Jos 10:11; Ps 78:47).

18:1-19 The first words, I will love thee, O Lord, my strength, are the scope and contents of the psalm. Those that truly love God, may triumph in him as their Rock and Refuge, and may with confidence call upon him. It is good for us to observe all the circumstances of a mercy which magnify the power of God and his goodness to us in it. David was a praying man, and God was found a prayer-hearing God. If we pray as he did, we shall speed as he did. God's manifestation of his presence is very fully described, ver. 7-15. Little appeared of man, but much of God, in these deliverances. It is not possible to apply to the history of the son of Jesse those awful, majestic, and stupendous words which are used through this description of the Divine manifestation. Every part of so solemn a scene of terrors tells us, a greater than David is here. God will not only deliver his people out of their troubles in due time, but he will bear them up under their troubles in the mean time. Can we meditate on ver. 18, without directing one thought to Gethsemane and Calvary? Can we forget that it was in the hour of Christ's deepest calamity, when Judas betrayed, when his friends forsook, when the multitude derided him, and the smiles of his Father's love were withheld, that the powers of darkness prevented him? The sorrows of death surrounded him, in his distress he prayed, Heb 5:7. God made the earth to shake and tremble, and the rocks to cleave, and brought him out, in his resurrection, because he delighted in him and in his undertaking.