I noticed a man whose opinion was followed by everyone, and no one acted contrary to what he said. I asked who he was, and I was informed that he was the Messenger of Allah (ﷺ). I said to him twice: "Alaikas- salam ya Rasul-Allah (May Allah render you safe)." He said, "Do not say: 'Alaikas-salamu.' This is the salutation to the dead (during the time of Jahiliyyah). Say, instead: 'As-salamu 'alaika (May Allah render you safe)."' I asked: "Are you the Messenger of Allah?" He replied, "(Yes) I am the Messenger of Allah, The One Who (Allah) will remove your affliction when you are in trouble and call upon Him, Who will cause food to grow for you when you are famine-stricken and call upon Him, and Who will restore to you your lost riding animal in the desert when you call upon Him." I said to him: "Give me instructions (to act upon)." He (ﷺ) said, "Do not abuse anyone." (Since then I have never abused anyone, neither a freeman, nor a slave, nor a camel, nor a sheep). He (ﷺ) continued, "Do not hold in contempt even an insignificant act of goodness because even talking to your brother with a cheerful countenance is an act of goodness. Hold up your lower garment half way to the leg, and at least above the ankles; for trailing it is arrogance, and Allah dislikes pride. And if a man attributes to you bad things he knows you possess, do not attribute to him bad things that you know he has for he will assume the evil consequences of his abuse."

[Abu Dawud and At-Tirmidhi].