If you meet a Muslim, you will say
Assalamu alaikum wa rahmatullahi wa barakatuhu.
May peace and blessings of Allah be upon you.
Virtue
On the authority of Hazrat Imran Ibn Hussain (RA), a man came to the Prophet (ﷺ) and said, Assalamu Alaikum. The Prophet (ﷺ) said, Ten (good deeds). Then another person came and said, Assalamu Alaikum wa Rahmatullah. The Prophet (ﷺ) said, Twenty (good deeds). Then another man came and said, Assalamu Alaikum Wa Rahmatullahi Wa Barakatuhu. The Prophet (ﷺ) said, Thirty (good deeds).
Reference: Sunan Tirmidhi, Hadith No: 2689
