3:17 Almighty Yahweh announced that He would honor those who feared Him as His own on the day He prepared His own possessions. This probably refers to the day of the Lord (cf. v. 2; 4:1, 3) when He will resurrect Old Testament saints and judge them. This will be when Jesus Christ returns to rule and reign on the earth. The faithful will receive a reward in His kingdom for their submission. He also promised to spare them as a man spares his own son. When Jesus Christ judges Old Testament saints, He will separate the sheep from the goats (Matt. 25:31-46). Here God described the sheep as His sons. He will spare them the humiliation and punishment that will be the lot of those who did not honor Him (vv. 14-15).
3:18 In that day it will be clear who behaved righteously and who behaved wickedly because Jesus Christ will reward the righteous and not reward the wicked among the Israelites. Then the true and the false servants of the Lord will be manifest. In Malachi's day, and in ours, the true motives of God's people are not obvious, but in the future they will become clear for many to see.
4:1 The Lord now elaborated on the day to which He had just referred (3:17).41This day of the Lord would be a day of judgment, which He compared to a fiery furnace in which all the arrogant and every evildoer would burn like chaff (or stubble; cf. 3:2-3, 15). That day would set them ablaze in that the Lord would set them ablaze in that day. He would so thoroughly purge them that they would be entirely consumed, like a shrub thrown into a hot fire is totally burned up, from root to branch (a merism of totality). The judgment of wicked unbelievers is in view (cf. Matt. 25:46). Later revelation clarified the time of this judgment, namely, the end of the Millennium (Rev. 20:11-15).
4:2 In contrast, the Israelites who feared Yahweh (1:14; 3:5, 16-17) would experience a reign of righteousness compared here to sunshine (cf. Isa. 60:1-3). The sun can blister, but it can also bless, and its blessing effect is in view here. The prophet evidently visualized the sunrays like the wings of a bird stretching over the earth. This righteous day would have a healing effect on the inhabitants of the earth, healing them, and the planet, from the harmful effects of past millennia of sin.
Some expositors have understood "the sun of righteousness"to be a messianic title, but it seems best to view it as a description of the day of blessing that Messiah will bring, the Millennium.42The figure of vigorous calves cavorting in open pasture after having been cooped up in a stall pictures the joy and freedom that the righteous will enjoy in that day (cf. Isa. 65:17-25; Hos. 14:4-7; Amos 9:13-15; Zeph. 3:19-20).
4:3 The righteous would also enjoy superiority over the wicked in that day, the opposite of the situation in Malachi's day. The wicked would be as ashes under their feet in that the wicked would suffer judgment and offer no resistance (cf. Isa. 66:24; Matt. 3:12; Mark 9:48). Almighty Yahweh was preparing that day, so it would inevitably come.
