It is narrated from Hazrat Anas (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Such people will come to you whose hearts will be even softer than yours." Accordingly, once the Ash'aris came, among whom was Hazrat Abu Musa Ash'ari (may Allah be pleased with him) as well. When they reached near Madinah Munawwarah, they began to recite rajaz poetry: "Tomorrow we will meet our friends, that is, Muhammad (peace and blessings be upon him) and his companions." Upon reaching there, they shook hands, and these were the very people who established the practice of shaking hands first.