The Lord Almighty answers, "I will send my messenger to prepare the way for me. Then the Lord you are looking for will suddenly come to his Temple. The messenger you long to see will come and proclaim my covenant." 1
References for Malachi 3:1
3.1 Mt 11.10; Mk 1.2; Lk 1.76; 7.27.
But who will be able to endure the day when he comes? Who will be able to survive when he appears? He will be like strong soap, like a fire that refines metal. 2
References for Malachi 3:2
3.2 Jl 2.11; Rev 6.17.
He will come to judge like one who refines and purifies silver. As a metalworker refines silver and gold, so the Lord's messenger will purify the priests, so that they will bring to the Lord the right kind of offerings.
Then the offerings which the people of Judah and Jerusalem bring to the Lord will be pleasing to him, as they used to be in the past.