"This is the son of Adam, and this is his life-span." And he placed his hand at the (height of the) nape of his neck, then he extended it (higher) and said:" From there is what is hoped for, from there is what is hoped for."
Jami` at-Tirmidhi Book 36, Hadith 31
← Previous Hadith "The Messenger of Allah (s.a.w) grabbed me on part of my body and said: 'Be in the world like a stranger or a passerby, and count yourself among the inhabitants of the grave.'" Ibn 'Umar said to me: "When you wake up in the morning, then do not concern yourself with the evening. And when you reach the evening, then do not concern yourself with the morning. Take from your health before your illness, and from your life before your death, for indeed O slave of Allah! You do not know what your description shall be tomorrow." (sahih)

Jami` at-Tirmidhi Book 36, Hadith 30 Next Hadith → "The Messenger of Allah (s.a.w) passed by us while we were repairing a hut of ours, so he said: 'What is this?' We said:"It has become weak, so we are repairing it.' He said: 'I do not think but that the matter (of life) is more in fleeting than that."

Jami` at-Tirmidhi Book 36, Hadith 32