Amen

A guest post by JS:

As is well known, Yom Kippur is the only time of the year where we recite "Baruch sheim k'vod malchu'to l'olam va'ed" (Blessed be the name of his glorious majesty forever and ever) out loud after saying the first verse of the Shma (Shma yisroel...).

However, we say this verse many times out loud during the avoda portion of the mussaf service which commemorates the temple service which took place on Yom Kippur. The source for this is actually this week's parsha, Ha'azinu. Moshe says, "When I call out the name of the Lord, ascribe greatness to our God."

Rashi notes that it is from this verse that the Rabbis learned that when God's name is declared (such as in in blessing), those who hear it need to "ascribe greatness to our God." In the temple, this was done by saying the verse "Baruch sheim k'vod malchu'to l'olam va'ed." However, outside of the temple, people instead said "Amen." This is why to this day we say "Amen" and only say "Baruch sheim k'vod malchu'to l'olam va'ed" on Yom Kippur when we recount what was said in the temple during the service on Yom Kippur.

But how does "Amen" fulfill the command to "ascribe greatness to our God"? The word "Amen" is related to the word "Emuna" which means faithfulness. Perhaps the answer is in the next verse in Ha'azinu:

"The deeds of the Rock (God) are perfect, for all His ways are just; a God of faithfulness, without injustice; He is righteous and upright."

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