תּוֹרָה קפד

When one speaks with one's fellow in the fear of Heaven — even though one's fellow does not receive it from him — even so one oneself receives an arousal from one's fellow. For through the words going out of one's mouth to one's fellow — the light returns to one.

And if one had spoken these words between oneself and oneself — it is possible one would not have been aroused from them at all. But through speaking them to one's fellow — even though the fellow was not aroused — even so one is oneself aroused. For they returned to one through the aspect of the rebound — like one who strikes and throws some object at a wall — the object returns to him.