Sahih al-Bukhari — Wedlock, Marriage (Nikaah) — Hadith No: 5211

Narrated Anas bin Malik:the Prophet (ﷺ) said, "If the people of the Scripture greet you, then you should say (in reply), 'Wa'alaikum (And on you)

Narrated `Abdullah bin `Umar:Allah's Messenger (ﷺ) said, "When the Jews greet you, they usually say, 'As-Samu 'alaikum (Death be on you),' so you should say (in reply to them), 'Wa'alaikum (And on you)

Narrated `Ali:Allah's Messenger (ﷺ) sent me, Az-Zubair bin Al-Awwam and Abu Marthad Al-Ghanawi, and all of us were horsemen, and he said, "Proceed till you reach Rawdat Khakh, where there is a woman from the pagans carrying a letter sent by Hatib bin Abi Balta'a to the pagans (of Mecca)." So we overtook her while she was proceeding on her camel at the same place as Allah's Messenger (ﷺ) told us. We said (to her) "Where is the letter which is with you?" She said, "I have no letter with me." So we made her camel kneel down and searched her mount (baggage etc) but could not find anything. My two companions said, "We do not see any letter." I said, "I know that Allah's Messenger (ﷺ) did not tell a lie. By Allah, if you (the lady) do not bring out the letter, I will strip you of your clothes' When she noticed that I was serious, she put her hand into the knot of her waist sheet, for she was tying a sheet round herself, and brought out the letter. So we proceeded to Allah's Messenger (ﷺ) with the letter. The Prophet (ﷺ) said (to Habib), "What made you o what you have done, O Hatib?" Hatib replied, "I have done nothing except that I believe in Allah and His Apostle, and I have not changed or altered (my religion). But I wanted to do the favor to the people (pagans of Mecca) through which Allah might protect my family and my property, as there is none among your companions but has someone in Mecca through whom Allah protects his property (against harm). The Prophet (ﷺ) said, "Habib has told you the truth, so do not say to him (anything) but good." `Umar bin Al-Khattab said, "Verily he has betrayed Allah, His Apostle, and the believers! Allow me to chop his neck off!" The Prophet (ﷺ) said, "O `Umar! What do you know; perhaps Allah looked upon the Badr warriors and said, 'Do whatever you like, for I have ordained that you will be in Paradise.'" On that `Umar wept and said, "Allah and His Apostle know best

Narrated Qatada:I asked Anas, "Was it a custom of the companions of the Prophet (ﷺ) to shake hands with one another?" He said, "Yes