ציטירנדיקער פּירוש אויף במדבר 11:2

ותאכל בקצה המחנה, “and it devoured at the outer edges of the camp.” Therefore the people complained against Moses (verse 2) since they were afraid that the fire would spread throughout the camp.

ויפל על פניו [AND WHEN MOSES HEARD IT,] HE FELL UPON HIS FACE because of the rebellion, for this was already the fourth offence on their part: when they sinned by worshipping the Golden Calf, it states, (Exodus 32:11) "And Moses besought [the Lord]”; in the case of the “people who complained”, (Numbers 11:1) it states: “and Moses prayed”; at the incident of the “spies”, (Numbers 14:13) “And Moses said unto the Lord, ‘When the Egyptians shall hear it ... [and now I beseech Thee etc.]”; but now at the rebellion of Korah, his hands sank down (he felt himself powerless) A parable! This may be compared to the case of a prince who sinned against his father and for whom his (the father’s) friend gained forgiveness once, twice, three times. When he offended for the fourth time the friend felt himself powerless, for he said, “ How long can I trouble the king? Perhaps he will not again accept advocacy from me!” (Midrash Tanchuma, Korach 4).

A Midrashic approach based on Tanchuma Korach 4: The words: “Moses fell on his face when he heard this” may be compared to a father whose son has become guilty of a major misdemeanor. He had a friend who would always intercede on behalf of that son and calm down the father’s irritation. When the son had become guilty of serious misconduct for a fourth time, the father’s friend felt that he could no longer defend the son’s conduct in good conscience by offering a variety of excuses. Here too, Moses had reached the stage where after having interceded on behalf of the people after the sin of the golden calf, and again when the people complained about their diet and the advantages of Egypt, and more recently when hey had rejected the Holy Land after hearing the report of the ten spies, Moses had come to the end of his rope as a defender of the people. This is why “he fell down.”