Assalamu `alaikum wa rahmatullah.
Thank you very much for your question.
Allah (Glorified be He) says in the Holy Qur’an:
They ask thee about the (final) Hour - when will be its appointed time? Say: "The knowledge thereof is with my Lord (alone): None but He can reveal as to when it will occur. Heavy were its burden through the heavens and the earth. Only, all of a sudden will it come to you." They ask thee as if thou Wert eager in search thereof: Say: "The knowledge thereof is with God (alone), but most men know not."
Surah 7 Verse 187
Only those wish to hasten it who believe not in it: those who believe hold it in awe, and know that it is the Truth. Behold, verily those that dispute concerning the Hour are far astray.
Surah 42 Verse 18
There are many hadiths on the Last Day and the Judgment:
The Prophet (peace be upon him) said, holding up his index and middle fingers:
'The times of my coming and the Hour are close like these two fingers.'
In another report he said:
'The Hour has almost come before me.'
This indicates that, we of the present day are not far away from the Hour. But, Allah alone knows the exact time of the Great Hour and He has not revealed it to anyone.
The Prophet (peace be upon him) said:
'There are five things which nobody knows except Allah.'
Then, he recited:
Verily the knowledge of the Hour is with God (alone). It is He Who sends down rain, and He Who knows what is in the wombs. Nor does any one know what it is that he will earn on the morrow: Nor does any one know in what land he is to die. Verily with God is full knowledge and He is acquainted (with all things).
Surah 31 Verse 34
When Angel Jibreel (peace be upon him) came to the Prophet (peace be upon him) in the guise of a Bedouin to ask him about Islam, iman (faith) and ihsan (excellence of faith), the Prophet answered his questions. But when he asked him about the Hour, he said:
'The one questioned about it knows no better than the questioner'
`Abdullah ibn Mas'ud – the companion of the prophet -reported that the Prophet said:
'Islam began as something strange, and it will revert to being strange as it was in the beginning; so happy news for the strangers.'
Someone asked, 'Who are the strangers?' He said, 'The ones who break away from their tribes for the sake of Islam.' (Reference: Collection of hadiths by Ibn Majah)
'Ali ibn Abi Talib reported that the Prophet (peace be upon him) said:
'If my ummah (nation) bears fifteen traits, tribulation will befall it.' Someone asked, 'What are they, O Messenger of Allah?' He said, 'When any gain is shared out only among the rich, with no benefit to the poor; when a trust becomes a means of making a profit; when paying zakat (alms) becomes a burden; when a man obeys his wife and disobeys his mother; and treats his friend kindly whilst shunning his father; when voices are raised in the mosques; when the leader of a people is the worst of them; when people treat a man with respect because they fear some evil he may do; when much wine is drunk; when men wear silk; when female singers and musical instruments become popular; when the last ones of this ummah curse the first ones - then let them expect a red wind, or the earth to swallow them, or to be transformed into animals.' (Reference: Collection of hadiths by Tirmidhi)
Also `Abdullah ibn `Umar said that the Prophet (peace be upon him) said:
'O Muhajirun, (emigrants from Mecca to Medina) you may be afflicted by five things; God forbid that you should live to see them. If fornication should become widespread, you should realize that this has never happened without new diseases befalling the people, which their forebears never suffered. If people should begin to cheat in weighing out goods, you should realize that this has never happened without drought and famine befalling the people, and their rulers oppressing them. If people should withhold zakat, you should realize that this has never happened without the rain being stopped from falling; and were it not for the animals' sake, it would never rain again. If people should break their covenant with Allah and His Messenger, you should realize that his has never happened without Allah sending an enemy against them, to take some of their possessions by force. If the leaders do not govern according to the Book of Allah, you should realize that this has never happened without Allah making them into groups and making them fight one another.’ (Reference: Collection of hadiths by Ibn Majah)
'Ali ibn Abi Talib also reported that the Prophet (peace be upon him) said:
'The Hour will come when leaders are oppressors, when people believe in the stars and reject al-qadar (the divine decree of destiny), when a trust becomes a way of making a profit, when people give to charity (sadaqah) reluctantly, when adultery becomes widespread - when this happens, then your people will perish.'
Here are a few other signs of the Last Day, mentioned by the Prophet (pbuh):
1. Barefooted shepherds will compete in owning tall buildings
2. Wine (intoxicants) will be consumed in great quantities
3. Earthquakes will increase
4. Bloodshed will increase
5. Power will be in the hands of those who do not deserve it
6. Women will far outnumber men
7. Arabia will become a land of gardens and rivers
There are a number of other signs too that come right before the end of time like sunrise from the West and the discovery of talking animals.
Judgment day, however is something, which we will all come to know potentially very soon. As soon as you die, the Day of Judgment starts for you, and you could die at any moment. This should be our utmost concern. But this must not make us fail to seek good in this world. We should live for the next world as if we were going to die in the next moment, but we should also live for this world as though we were going to live forever.
Allah knows best.
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