Some rough bedouins used to visit the Prophet (ﷺ) and ask him, "When will the Hour be?" He would look at the youngest of all of them and say, "If this should live till he is very old, your Hour (the death of the people addressed) will take place." Hisham said that he meant (by the Hour), their death.

“The Messenger of Allah (ﷺ) came out one day to the people, and a man came to him and said: ‘O Messenger of Allah, when will the Hour be?’ He said: ‘The one who is asked about it does not know more than the one who is asking. But I will tell you of its portents. When the slave woman gives birth to her mistress, that is one of its portents. When the barefoot and naked become leaders of the people, that is one of its portents. When shepherds compete in constructing buildings, that is one of its portents. (The Hour) is one of five (things) which no one knows except Allah.’ Then the Messenger of Allah (ﷺ) recited the words: “Verily, Allah, with Him (alone) is the knowledge of the Hour, He sends down the rain, and knows that which is in the wombs. (to the end of the Verse).”

A bedouin came to the Prophet (ﷺ) and said, "O Allah's Messenger (ﷺ)! When will The Hour be established?" The Prophet (ﷺ) said, "Wailaka (Woe to you), What have you prepared for it?" The bedouin said, "I have not prepared anything for it, except that I love Allah and H is Apostle." The Prophet (ﷺ) said, "You will be with those whom you love." We (the companions of the Prophet (ﷺ) ) said, "And will we too be so? The Prophet (ﷺ) said, "Yes." So we became very glad on that day. In the meantime, a slave of Al-Mughira passed by, and he was of the same age as I was. The Prophet (ﷺ) said. "If this (slave) should live long, he will not reach the geriatric old age, but the Hour will be established."

“When this Ayah was revealed: ‘Then on that Day, you shall be asked about the delights!’ the people said: ‘O Messenger of Allah! About which delights shall we be asked? For they are only the two black things, while the enemy is present and our swords are (at the ready) upon our shoulders?” He said: ‘But it is what shall come.’”

I heard Allah's Messenger (ﷺ) as saying this one month before his death: You asked me about the Last Hour whereas its knowledge is with Allah. I, however, take an oath and say that none upon the earth, the created beings (from amongst my Companions), would survive at the end of one hundred years.