Al-Tirmidhi HadithHadith 118 Narrated byAbuHurayrah

Allah's Messenger (peace be upon him) said: When Allah created Adam, He touched his back, and there fell from his back every soul that He would create from his offspring till the Day of Resurrection and He created between the two eyes of every person a gleam of light. Then He presented them to Adam who said: My Lord who are they? He (the Lord) said: They are your offspring. He (Adam) saw a person from amongst them and he felt attracted towards him and the sparkle of light between his two eyes. He said: My Lord, who is he? (The Lord) said: It is David. He (Adam) said: My Lord, what span of life have you allotted to him? He replied: Sixty years. He said: My Lord, enhance his age from my age (to the extent of forty years). Allah's Messenger (peace be upon him) said: When Adam completed his age life-span with only forty years remaining, there came to him the angel of death. Thereupon Adam said: Are there not forty years left in my life-span? The angel said: Did you not confer your son (forty years). Adam denied it and so did his offspring. Adam forgot and ate (the fruit) of the tree and so his offspring also forgot and he (Adam) committed an error and so did his offspring commit an error.