صحيح مسلم

Anas b. Malik reported that a person asked Allah's Messenger (ﷺ): When would the Last Hour come? Thereupon Allah's Messenger (way peace be upon him) kept quiet for a while. Then looked at a young boy in his presence belonging to the tribe of Azd Shanu'a and he said: If this boy lives he would not grow very old till the Last Hour would come to you. Anas said that this young boy was of our age during those days.