And now this commandment is for you, O priests. [Malachi 2:1]
Imagine this: a man whose background we know nothing of stepped inside the temple and gave the priests a lecture in front of everyone. The intention of the lecture was to point out their sins, and point them to proper worship. Given the respect the people had for the priests, such an action must have been shocking to those present.
Please note that the above is part of my imagination. When Malachi lectured the priests, it might not be in the temple, it could be in the marketplace, or elsewhere.
I think that was a foreshadow of Jesus. When Jesus stepped into the temple, He chased away those peddlers in order to cleanse the temple, so that worship could be done properly. Jesus spoke out against the Pharisees and priests publicly, pointing out their hypocritical front. Sadly instead of repenting, they plotted to kill Him.