On verse 14:4, Rashi says that Moshe Rabbeinu told Klal Yisrael to travel towards the Egyptians. While this move made no sense, the Torah says “v’yaasu kein” – and they listened without questioning Moshe. Rashi explains that Klal Yisrael said “We rely only on the words of the son of Amram.” The Tiferes Shlomo asks “Why was Moshe referred to, at this time, as the ‘son of Amram’ rather than by his name ‘Moshe’”? The Tiferes Shlomo notes that during the splitting of the sea, there seems to be a great emphasis on the believing Moshe, aside from trusting in Hashem, as the Torah says “they believed in Hashem, and in Moshe his servant.” Again, the Tiferes Shlomo asks “What does it mean to believe in the servant? The servant is just an extension of the belief in Hashem.”
He answers these questions by stating we have an obligation to trust gedolei Yisrael. The gemora tells us “chacham adif m’navi”, “a scholar is greater than a prophet”. The Tiferes Shlomo explains that, when a prophet tells us something, he is the voice of Hashem – he is the oracle presenting the Divine thought to us. However, when the chacham – a man who has reached a high level in Torah and piety – tells us something, we are obligated to listen to it. This is true even if he tells us clearly it is not something that he is relaying directly from Hashem.
Let us return to the questions at hand. Splitting of the sea was a test for klal Yisrael to see if they really believed. Full belief must include believing in what the gedolei Yisrael say, even if it is not Hashem’s word. Therefore, Rashi did not use the name “Moshe Rabbeinu”, which implies he is the emissary of G-d, but instead called him “Ben Amram”, implying that while the words were not coming as a directive from Hashem, nevertheless he spoke words which were G-dly and we were obligated to heed them. This is why the belief in “Moshe Avdo”, the man dedicated to ideals of Hashem, is emphasized as a separate belief and positive attribute of Klal Yisrael.
This subjugation to our mentors is demanded of us, not only in the beis hamedrash, but outside of it as well. Just as when Moshe told Bnei Yisrael to go towards the enemy, which seemed to be an obvious mistake, Bnei Yisrael accepted it unquestionably, and were praised for this attribute, we too can accept our gedolim’s words and overcome our natural “better judgement” and create our own miracle of krias yam suf.