A Shiite scholar by the name of Fayz Kashani who was an unmatched Muhadith, wrote in one of his books: a person came to Prophet and asked him: O the Messenger of Allah! What is welfare and felicity? The Holy Prophet of Islam (peace be upon him and his progeny) answered him in two words –which indeed is a book; His eminence said: it is to have a long life and spend your life worshiping Allah Almighty.
source : erfan.ir
