The entire assembly of the Bnei Yisrael exited from before Moshe[2]
Isn’t this pointing out the obvious? From where else could they exit? They had all been gathered in front of Moshe, who was relating Hashem’s instructions to them. Anywhere they were going, it was away from where they had been standing before Moshe!
For that matter, why mention their taking leave of Moshe altogether, rather than just transitioning to the next topic?
We can make sense of this in light of the gemara’s dictum,[3] “A disciple who takes leave of his teacher should not do an about face and exit. Rather, he should turn sideways and continue out.” We can see this in our pasuk, i.e. when people exited from before Moshe, they did not turn around, but walked backwards. Thus, even in exiting, they remained before – that is, facing – Moshe.
By underscoring “the entire congregation of the Bnei Yisrael,” the Torah gives us another level of understanding. In the aftermath of the chet ha-eigel, the Bnei Yisrael had distanced themselves from the eirev rav. That was the group which had instigated the worship of the golden calf. Specifically, they noted the disappearance of Moshe, and asked for “gods that will go before us.” There was more than a hint of their agenda in this phrase. They were looking for gods who would be led by them, who would take their cues from their wants, desires, and religious notions. They were going to create gods in their image – if not literally, then conceptually. The “leadership” of the gods they wished to serve would only be a reflection of where they wanted to go. They did not stand before their intended gods; their gods stood before them
Having purged themselves of this noxious influence, the Bnei Yisrael understood that Moshe was to be a real leader. They would follow his lead, rather than the reverse. They stood before a Moshe who would show them how to act and where to to, rather than a figurehead Moshe standing before them.