The Messenger of Allah ﷺ said, "The people of Yemen have come to you. Their hearts are softer than yours, and they were the first to introduce the handshake."
أن رسول الله ﷺ قال: أتاكم أهل اليمن، هم أرق قلوبا منكم، وهم أول من جاء بالمصافحة.
Narrated by Abu Dawud (5213), Ahmad (13212), and Bukhari in Adab al-Mufrad (967), all through routes from Hammad bin Salama, from Humayd, from Anas, as mentioned. Abu Dawud's version does not contain, "They are more tender-hearted than you." Its chain of transmission is sahih.The statement, "They were the first to introduce handshaking," is from the words of Anas himself, as is made explicit in Ahmad's version (13264), from Affan, who said, Hammad bin Salama narrated to us, he said, Humayd informed us, from Anas, who said, when the people of Yemen arrived, the Messenger of Allah ﷺ said, "The people of Yemen have come to you, they are more tender-hearted than you." Anas said, and they were the first to introduce handshaking.