Several times when Moses is challenged in the Torah and he fears for his life, the text says Vayipol Al Panav “And he fell on his face.” What does this mean? Does it literally mean he fell flat on his face? That must have hurt and we are commanded not to hurt ourselves.
I don’t think we are meant to take it literally. It could mean to bow down in an act of submission. In which case, it would be what we call Nefillat Apayim when we bow our heads on to our arms when we say Tahanun, prayers for forgiveness during normal weekday prayers. Or when on Yom Kippur we bow down head to the ground to God. We don’t actually fall on our faces. But our heads are bowed in submission.
So, did Moses fall on his face before God as a way of saying “I have failed you?” Perhaps he was submitting to his accusers, something that seems very unlikely.
The first time it is used in the Torah is the case of Cain who killed his brother. When his sacrifice was not accepted, it says, “His face fell.” In other words, his face betrayed his inner feelings. He was angry, insulted, disappointed and it showed.
Our faces really do betray us. A clever face reader can tell a huge amount about a person from his or her facial expressions. That’s one of the tricks magicians, gypsy palm readers, even kabbalists use! I have often heard the expression “You should only see your face now.” We blush, blink or twitch. We have what card players call a “tell.” It takes a great deal of discipline to control our facial expressions which most of us do not have.
So, what Moses was showing, was how angry he was at these stupid, arrogant, ungrateful self-serving rebels and perhaps also his fear that God might, as he threatened, destroy those who attacked his messenger on earth.