Abu Jurayy Jabir b. Sulaim said

I came to Medina and saw a man whose opinion was followed by the people, for he said nothing without their acting on it. I asked who he was, and when I was told that he was Allah's Messenger ﷺ, I said twice, “Upon you be peace, Messenger of Allah .” He replied, ‘Do not say, “Upon you be peace,’ for that is the salutation to the dead, but say, ‘Peace be upon you’.” I asked him if he was Allah's Messenger ﷺ, and he replied, “I am the messenger of Allah who, if injury befalls you and you call on Him, will remove it; if a year of famine comes upon you and you call on Him, will make things grow; if you lose your riding-beast in a barren land or desert and call upon Him, will restore it to you.” I asked him to give me an injunction, and he said, “Do not revile anyone.” After that I never reviled a freeman or a slave, a camel or a sheep.” He said, “And do not consider any act of kindness insignificant, for looking pleasantly at your brother when you speak to him is an act of kindness. Wear your lower garment halfway up to the knee, but if you dislike that, let it go down to the ankles; on no account, however, must you let it trail, for that is a kind of pride, and Allah does not like pride. If anyone reviles or reproaches you for something he knows about you, do not reproach him for something you know about him, for the mischief of that will lie at his door.” Abu Dawud transmitted it, and Tirmidhi transmitted the part about the salutation. A version has, “The reward of that will be yours and its mischief will be his.”