It really matters to show sincere repentance. Sinning is terrible, especially when you have sinned together as a church community. In addition to fasting together, the leaders must make their repentance visible. Joel points out the place where the leaders are to show their repentance, their conduct that goes with it, and the words to be used. The leaders are to weep as they stand as closely as possible to the temple (the vestibule,
which is the Holy Place, the primary area of the temple). They do not go inside, because then the people cannot see their conduct. But they do approach God as closely as possible, because God alone is able to save. The argument they may allege is: destruction of the people, however deserved, would harm God’s name in the world. This is an argument that counts (see e.g., Numbers 14:1–45).
17 Between the vestibule and the altar let the priests, the ministers of the LORD, weep and say, “Spare your people, O LORD, and make not your heritage a reproach, a byword among the nations. Why should they say among the peoples, ‘Where is their God?’”