And I will be a swift witness against the sorcerers— God tells them, that he will hasten the day of his vengeance, and that it shall come speedily upon those whose sins are become epidemical; and if they refuse to repent on the preaching of the Gospel, he will proceed to destroy the nation utterly. This may also farther refer to the second coming of our Lord to judge both quick and dead. See Lowth and Calmet.
Related Commentaries of Malachi 3:5
Malachi 3:5
5 And I will come near to you to judgment; and I will be a swift witness against the sorcerers, and against the adulterers, and against false swearers, and against those that oppressb the hireling in his wages, the widow, and the fatherless, and that turn aside the stranger from his right, and fear not me, saith the LORD of hosts.