'Abdullah bin Salam said:
"When the Messenger of Allah (s.a.w) arrived- meaning in Al-Madinah – the people came out to meet him. It was said that the Messenger of Allah (s.a.w) had arrived, so I went among the people to get a look at him. When I gazed upon the face of the Messenger of Allah (s.a.w), I knew that this face was not the face of a liar. The first thing that he spoke about was that he said: 'O you people! Spread the Salam, feed(others), and perform Salat while the people are sleeping; you will enter Paradise with(the greeting of) Salam.'" (Sahih) (FR)
English reference (FR): Vol. 4, Book 11, Hadith 2485 (FR)
Arabic reference (FR): Book 37, Hadith 2673 (FR)