But who {d} may abide the day of his coming? and who shall stand when he appeareth? for he is like a refiner's fire, and like fullers' soap:

(d) He shows that the hypocrites who wish so much for the Lord's coming will not remain when he draws near: for he will consume them, and purge his own and make them clean.

Wesley's Notes

3:2 Abide - Who shall be able to stand under the weight of those crosses which in that day, will fall on all sorts of men? The day - This day was from his preaching, 'till the utter destruction of Jerusalem, about seventy years after the birth of Christ. A refiner's fire - Some are like metals, which nothing but a fierce fire can purge, such fire shall the troubles of these days be. Fuller's soap - As boiling waters, into which, spotted cloaths are thrown, and as the rubbing of them with soap; so that day will prove to all, a day of great trial, to purge and refine.

Jamieson-Fausset-Brown Bible Commentary

2. (Mal 4:1; Re 6:16, 17). The Messiah would come, not, as they expected, to flatter the theocratic nation's prejudices, but to subject their principles to the fiery test of His heart-searching truth (Mt 3:10-12), and to destroy Jerusalem and the theocracy after they had rejected Him. His mission is here regarded as a whole from the first to the second advent: the process of refining and separating the godly from the ungodly beginning during Christ's stay on earth, going on ever since, and about to continue till the final separation (Mt 25:31-46). The refining process, whereby a third of the Jews is refined as silver of its dross, while two-thirds perish, is described, Zec 13:8, 9 (compare Isa 1:25).

Matthew Henry's Concise Commentary

3:1-6 The first words of this chapter seem an answer to the scoffers of those days. Here is a prophecy of the appearing of John the Baptist. He is Christ's harbinger. He shall prepare the way before him, by calling men to repentance. The Messiah had been long called, He that should come, and now shortly he will come. He is the Messenger of the covenant. Those who seek Jesus, shall find pleasure in him, often when not looked for. The Lord Jesus, prepares the sinner's heart to be his temple, by the ministry of his word and the convictions of his Spirit, and he enters it as the Messenger of peace and consolation. No hypocrite or formalist can endure his doctrine, or stand before his tribunal. Christ came to distinguish men, to separate between the precious and the vile. He shall sit as a Refiner. Christ, by his gospel, shall purify and reform his church, and by his Spirit working with it, shall regenerate and cleanse souls. He will take away the dross found in them. He will separate their corruptions, which render their faculties worthless and useless. The believer needs not fear the fiery trial of afflictions and temptations, by which the Saviour refines his gold. He will take care it is not more intense or longer than is needful for his good; and this trial will end far otherwise than that of the wicked. Christ will, by interceding for them, make them accepted. Where no fear of God is, no good is to be expected. Evil pursues sinners. God is unchangeable. And though the sentence against evil works be not executed speedily, yet it will be executed; the Lord is as much an enemy to sin as ever. We may all apply this to ourselves. Because we have to do with a God that changes not, therefore it is that we are not consumed; because his compassions fail not.