NOTES for Mal 3:1-4
Whom does Malachi mean when he speaks of the messenger of the covenant (the ‘angel of the covenant’)? The Book of Malachi gives no answer to this question. We can only conjecture what the prophet is speaking of. One thing is clear: something must happen before the Messiah comes. Someone must appear who will prepare God's people spiritually to receive the coming Messiah. Whether this is an angel or a human being is not so important. What matters is the preparation itself. And judging by the prophet's words, quite serious preparation is needed. In describing it, Malachi uses the language of traditional prophetic symbolism. Its meaning is clear: the people must be purified and spiritually renewed. Otherwise they cannot meet the Messiah.
The Gospel accounts of John the Baptist are written in such a way that it is hard not to recognise this messenger of the covenant in him. He is not an angel but a human being. Yet he does precisely what Malachi describes. John himself, however, says that the people's true purification still lies ahead. Nevertheless, he calls the people to repentance, cleansing from sin and conversion. Like Malachi, he understands that no one is pure and ready to meet the Messiah. John calls the Pharisees and Sadducees, who deep down consider themselves to be so, a ‘brood of vipers’.
This is not abuse but a statement of fact. John is clearly alluding to the serpent who once, in the Garden of Eden, tempted the first human beings with the illusory possibility of living without God. And a person who regards righteousness as a property or quality of their nature, even an acquired quality, makes the same mistake. There are no people in the world who are pure and free from sin, not because it is impossible to be freed from sin and its consequences, but because fallen humanity cannot help sinning.
John, unlike those same Pharisees, understands this. So does Malachi, who speaks of the need to purify the people. One cannot become righteous by nature, at least not before that nature itself has been completely transformed. But one can abide in a state of righteousness. That means a state of constant resistance to one's own sin. A state of constant purification. Until the journey ends in the Kingdom. In the Kingdom, where there will no longer be any place for sin.