Ibn ‘Abbaas (may Allah be pleased with him) reported that ‘Umar ibn al-Khattaab entered upon the Messenger of Allah (peace and blessings of Allah be upon him) when he was lying on a mat of palm fibres that had left marks on his side. ‘Umar said, “O Messenger of Allah, why do you not get something more comfortable than this?” He (peace and blessings of Allah be upon him) said: “What do I have to do with this world? My relationship with this world is like that of a traveller on a hot summer’s day, who seeks shade under a tree for an hour, then moves on.”
(Reported by Ahmad and al-Haakim. Saheeh al-Jaami’, 5545).