Sahih Bukhari Volume 008, Book 076, Hadith Number 446.
Narated By Sahl bin Sa'd : I heard Ibn Az-Zubair who was on the pulpit at Mecca, delivering a sermon, saying, "O men! The Prophet used to say, "If the son of Adam were given a valley full of gold, he would love to have a second one; and if he were given the second one, he would love to have a third, for nothing fills the belly of Adam's son except dust. And Allah forgives he who repents to Him." Ubai said, "We considered this as a saying from the Qur'an till the Sura (beginning with) 'The mutual rivalry for piling up of worldly things diverts you...' (102.1) was revealed."