expression
preaching to the deaf; like talking to a wall
Idiomatic expression meaning that advice or reasoning is wasted on someone who cannot or will not understand. Literally 'chanting the nembutsu into a horse's ear'.
See also: 念仏
彼に何度言っても馬の耳に念仏だ。
No matter how many times I tell him, it's like talking to a wall.
Telling kids about the importance of saving money might be like preaching to the deaf.