It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that he heard the Messenger of Allah (peace and blessings be upon him) say: "A time will surely come upon the people when you will envy a man for being lightly burdened (having little wealth) just as today he is envied for having much wealth and many children, until one of you passes by his brother's grave and rolls about on it as an animal rolls about in its pasture, and says: Would that I were in his place! He will have no longing for Allah, nor any good deed that he has sent ahead; rather (this wish) will be because of the affliction that has befallen him."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9742