What is consequence of "b'Rav Am Hadras Melech"?
Brachos 53a: It is better that one bless for everyone than for everyone to bless by himself.
Pesachim 64b: A Kohen received the blood of Korban Pesach, and gave it to another Kohen, who gave it to another [until the end of the line]. Many Kohanim were used, to fulfill b'Rav Am Hadras Melech 1 .
Megilah 27b: If you will say that one may not sell a public [Beis ha'Keneses] to an individual, for you lower its Kedushah, likewise one may not sell from a big city to a small city.
Rashi: When a big Tzibur merit, it is Hashem's glory.
R. Yonah: One who fears Hashem is much more secure and serene than the king is, for his trust is not in people. The king's security depends on people.
Malbim: A gathering with a king is called an Am. (This distinguishes it from a Goy.) Hadar is external beauty; the king's Hadar is according to the size of the nation.
Mishnah Berurah (90:28): If there are two Batei Kenesiyos, is better to pray in the one with more people.
Bi'ur Halachah (426:2 DH Ela): If later one will be able to say Kidush Levanah amidst many people, one should wait until the 10th of the month. Even three is called b'Rav Am.
Similarly, the Stam Tana holds that some Kohanim bring limbs of the Tamid onto the ramp, and others put them on the fire (Yuma 26a). The son of Marsa bas Baisus would take two thighs of a big ox [to put them on the Mizbe'ach] by himself, and the other Kohanim did not let him (Sukah 52b).
What is "uv'Efes Le'om mi'Tachas Razon"?
Rashi: When people do not cling to Him, his authority is lacking. It is as if He gives from His honor to foreign gods, and gives to the nations authority over His children.
Malbim: A gathering with a common creed is called Le'om. Rozenim are officers of counsel. Yo'etz counsels in matters of the country, and their counsel is exposed. Rozenim are in hidden matters; their appointment is also over matters of the creed and its laws - "v'Rozenim Yechokeku Tzedek" (8:15). A Razon appointed over the laws of the creed over an Am that is not Le'om, he does not do anything.
