Abu Dawud
Jihad
Book Number: 008 / Hadith Number: 2522
Narated By Abdullah ibn Amr ibn al-'As : A man came to the Apostle of Allah (pbuh) and said: I came to you to take the oath of allegiance to you on emigration, and I left my parents weeping. He (the Prophet) said: Return to them and make them laugh as you made them weep.