To teach by example; to instruct through one's actions rather than through words—literally 'teach with one's back.'
新人には口で指示するより背中で教える方が分かりやすいこともある。
For newcomers, it's sometimes easier to learn by example than by verbal instructions.
彼は叱る代わりに自分の働きぶりで背中で教えるタイプの上司だ。
He's the kind of boss who teaches by example with his own work rather than scolding.
祖母は言葉少なだったが、背中で教えることが多かった。
My grandmother said little, but often taught by example.