Ibn 'Umar (RAA) narrated, 'Allah's Messenger (ﷺ) took hold of my shoulders and said, "Be in this world as though you were a stranger or a passerby." Ibn 'Umar used to say, "If you are alive in the evening, do not expect to be alive till the morning and if you are alive in the morning do not expect to be alive till the evening, and take from your health for your sickness, and from your life for your death." Related by Al-Bukhari.
English reference: Book 16, Hadith 1513
Arabic reference: Book 16, Hadith 1470