I have seen books (to be honest they were novels) like Bodie Thoene use the SH'ma as if its used in battle, or it gave them a sense of strength in peace time, like a reminder. Like in America they say "remember the Alamo" during battle MAYBE it seems to be the same kind of team booster during peace time yet also it seems to be used in other moments.
How is Sh'ma used in what cases would it be used?