God's judgment on the wicked,
Malachi 4:1 For behold, the day cometh, that shall burn as an oven; and all the proud, and all that do wickedly, shall be stubble: and the day that cometh shall burn them up, saith the LORD of hosts, that it shall leave them neither root nor branch.
and his blessing on the good.
Malachi 4:2 But to you that fear my name, shall the Sun of righteousness arise with healing in his wings; and ye shall go forth, and grow up as calves of the stall. Malachi 4:3 And ye shall tread down the wicked; for they shall be ashes under the soles of your feet in the day that I shall do [this], saith the LORD of hosts.
He exhorteth to the study of the Law,
Malachi 4:4 Remember ye the law of Moses my servant, which I commanded to him in Horeb for all Israel, [with] the statutes and judgments.
and telleth of Elijah's coming and office.
Malachi 4:5 Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the LORD: Malachi 4:6 And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers, lest I come and smite the earth with a curse.