This is the “burden” (i.e., the difficult prophecy) that G-d gave to Israel through the prophet Malachi. (Some say Malachi was in fact Ezra. The name Malachi means “my messenger.” Malachi and Ezra lived at the same time and addressed many of the same issues.) G-d says that He loves Israel. If they should question this, they need only compare their lot with Edom’s. (Israel and Edom are descended from brothers, Jacob and Easu.) Edom has been demolished and G-d will not allow them to rebuild. But they will see that Israel will be rebuilt!
A son respects his father and a servant respects his master, so why don’t the Jews give G-d proper respect? The kohanim (priests) are negligent when it comes to their responsibility to educate the people. And how have they disrespected G-d? They offered sacrifices that were sick and blind. They would never give a human ruler such an animal as a gift, so why do they disrespect G-d with such offerings? Do they think He’ll heed their prayers when they treat Him so lightly? If only there were one person who would take a stand! G-d doesn’t want their half-hearted service.
Even the other nations recognize that there is a Creator over their idols, but the Jews disgrace Him by saying that the sacrifices of His altar are insignificant. G-d curses those who would justify and make excuses, offering a lesser animal as a sacrifice rather than the best of his flocks. G-d is the Great King; if the other nations recognize this, how much more should the Jews!
Through Malachi, G-d charges the kohanim (priests) with accepting unfit sacrifices. If they do not listen, He will curse what otherwise would be blessed. In fact, He has already begun to do so! G-d will stop the grain from growing and G-d will toss the manure of their sacrifices in their faces. G-d reminds the kohanim how He forged a covenant specifically with the Tribe of Levi, to administer to Him in the Temple. Pinchas, who was zealous for G-d, earned this covenant, which is called one of peace, for himself and his descendants. The kohanim should be pure, and they should be like representatives of G-d on Earth.