Malachi 3:1-7 The Coming Messenger, And A Call To Repentance.
There are two messengers here. One would come as another prophet to prepare for the other. The Messiah would come to His house as the Messenger of the covenant (v. 1). The first messenger was John the Baptist (Is. 40:3; Mt. 3:3; 11:10; Mk. 1:2; Lk. 1:76; 7:27; Jn. 1:23). The Messenger of the covenant will be “like a refiner’s fire and like launderer’s soap” (v. 2 Cf. 4:1; I Cor.3:13-15). He would purify the sons of Levi, “that they may offer to the LORD an offering in righteousness” (v. 3 Cf. Is. 1:25; Dan. 12:10; Zech. 13:9). When the priests are purified then the offering “will be pleasant (or pleasing) to the LORD” (v. 4 Cf. 1:11).
The LORD of hosts Himself would be a witness for judgment against those who break His law, because they did not fear Him (v. 5 Cf. Ex. 22:22; Lev. 19:12-13; Zech. 5:4; Js. 5:4, 12). The covenant has always held out mercy and grace, because the LORD set His love upon His own. This would not change, because the LORD has always had a remnant (v. 6 Cf. Nu. 23:19-20; Lam. 3:22-24; Rom. 11:29; Js. 1:17). The backsliding of Malachi’s day went all the way back to the patriarchs. However, if they repented, which meant turning from their wicked ways, and also turning to the LORD, He would return to them, but they were ignorant of true repentance (v. 7 Cf. 1:6; Zech. 1:3; Acts 7:51).