I must be missing something, but I do not understand the din that someone who davens slichos should serve as shat"z for the rest of the tefilos of the day because "ha'maschil b'mitzvah omrim lo gmor." Why not say every day that whoever daven shacharis should serve as shat"z for the rest of the day because "ha'maschil b'mitzvah omrim lo gmor?" Obviously we don't say that. So why is there such a din by slichos?
Rashi quotes the view of R’ Yosi that the “ha’yarei v’rach ha’leivav” who is given a deferment from battle (20:8) is someone who is afraid because of the “aveiros b’yado.” Doesn’t the peshuto shel mikra fit much better with R’ Akiva’s view that we are speaking “k’mashma’o” (as Rashi writes) about someone who is simply afraid of going to war? Why does R' Yosi think that's not the fear the pasuk is talking about?
Sefas Emes: Of course the pasuk is speaking about someone who is afraid to go to war -- even R’ Yosi agrees that’s what the words mean. What R’ Yosi (and Rashi, by quoting him) is explaining is the cause of that fear -- where does it come from? Not from cowardice, but “mei’aveiros b’yado,” because the person is weighed down by aveiros.
Why is that such a bad thing? Isn’t yiras shamayim an ideal?
It could be that the key word here is “b’yado” – a person should not be narrowly focused on their own plight to the exclusion of everyone and everything else.
The Sefas Emes has a different approach, based on an explanation he has in a few places (posted here) as to how Sarah, when challenged by G-d, could deny laughing at the malach’s promise that she would have a son. He explains that teshuvah can literally erase the past – it is like the wrongdoing never happened. When a person is a true yarei shamayim, it inspires that type of teshuvah. When Sarah laughed, she immediately realized her error and regretted it; Sarah immediately did complete teshuvah. “Lo tzachakti” – Sarah was correct in saying that she did not laugh, because her teshuvah erased it -- “ki yarei’ah,” because she was on a level of yiras shamayim that engenders such great teshuvah.
Someone who is “yarei mei’aveiros b’yado” lacks that true yiras shamayim. To the contrary, the obsession with wrongdoing indicates a failure to do full teshuvah and rise above the past.