In our study of Malachi chapter four, we will look at the end of the age of the law and the dawn of grace. As the final book of the Old Testament, it contains the final words from God before a four hundred year period of silence.
"'Surely the day is coming; it will burn like a furnace. All the arrogant and every evildoer will be stubble, and that day that is coming will set them on fire,' says the Lord Almighty. 'Not a root or branch will be left to them.'" NIV translation
Here, God tells the people of the coming harvest of the earth. In this harvest, those who did not accept Jesus Christ as their Lord and Savior will be gathered and cast into judgment. This is also what John saw in Revelation 14.
"'But for you who revere my name, the sun of righteousness will rise with healing in its wings. And you will go out and leap like calves released from the stall.'" NIV translation
An animal that has been caged goes wild with joy when they are released. We too, will run and jump for joy because of the freedom that comes through Jesus Christ. Here, Jesus is presented as the sun of righteousness and He brought healing to us from the penalty of our sin. This was a prophecy at the time of Malachi that has been fulfilled today.
"'Then you will trample down the wicked; they will be ashes under the soles of your feet on the day when I do these things,' says the Lord Almighty." NIV translation
We will reign victorious with Jesus Christ and God has promised to put the enemy under our feet. Today, it seems like those who do evil have the upper hand but we can take comfort in this promise that, in due time, they will be dealt with.
"'Remember the law of my servant Moses, the decrees and laws I gave him at Horeb for all Israel.'" NIV translation
The sun is setting on the Old Testament with the close of the book of Malachi. Just as in nature, when the sun sets there is a period of darkness. Between the Old and New Testament was a period of about four hundred years in which God did not speak to His people (period of darkness). That is why God is reminding them here to remember the laws that He had given them.