This same thing happens to us in everyday life. Just because someone trusts me with their secrets doesn't mean I should trust everyone I meet with mine. If I'm smart, I keep quiet when I hear something. But the other person goes and tells everyone what they heard. When I find out what happened, if I'm like him, I decide to get revenge. I tell everyone his secrets. I upset other people and get upset myself. But if I remember that one person can't really harm another, and that everyone's actions only hurt or help themselves, then I make sure I don't act like him. I still suffer from what happens, but only because of my own foolish talking.
Something of this kind happens to us also generally. Now as this man has confidently intrusted his affairs to me, shall I also do so to any man whom I meet? (No), for when I have heard, I keep silence, if I am of such a disposition; but he goes forth and tells all men what he has heard. Then, if I hear what has been done, if I be a man like him, I resolve to be revenged, I divulge what he has told me; I both disturb others, and am disturbed myself. But if I remember that one man does not injure another, and that every man's acts injure and profit him, I secure this, that I do not anything like him, but still I suffer what I do suffer through my own silly talk.