وَعَنِ ابْنِ عُمَرَ قَالَ: أَخَذَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِبَعْضِ جَسَدِي فَقَالَ: «كُنْ فِي الدُّنْيَا كَأَنَّكَ غَرِيبٌ أَوْ عَابِرُ سبيلٍ وعُدَّ نفسَكَ فِي أهل الْقُبُور» . رَوَاهُ البُخَارِيّ
Ibn Umar, may Allah be pleased with him, narrates that the Messenger of Allah, peace and blessings be upon him, took hold of a part of my body and said: "Live in this world as if you are a stranger or a traveler, and count yourself among the inhabitants of the graves (the dead)." Narrated by al-Bukhari.