One of the unseen matters that happened after the Prophet’s death was the news about Um Haraam bint Milhan. The Prophet (peace be upon him) told her, ‘Some people from my nation were shown to me [in my dream], fighting in the cause of Allah and riding across the sea like kings on thrones.’ Um Haraam said, ‘O Prophet, pray to Allah to make me one of them.’ The Prophet prayed for her, and then he slept again and later woke up, smiling. Um Haraam said to him, ‘What makes you smile, O Prophet?’ He said, ‘Some people of my nation were shown to me, fighting in the cause of Allah and riding across the sea like kings on thrones,’ as he had said the first time. Um Haraam said, ‘O Prophet, pray to Allah to make me one of them.’ He said, ‘You will be one of the first.’ And she traveled by sea at the time of Mu'awiyah ibn Abu Sufyan and later fell from her mount when she came out of the sea and died related by Al-Bukhari Who told the Prophet (peace be upon him) what would happen in the future?! Who told him that his nation would partake in a naval battle in the future, and that Um Haraam bint Milhan would live long enough to attend and partake in this battle?! It is Allah (Glorified is He).
Some of the unseen matters that happened after the Prophet’s death were the six important events which the Prophet (peace be upon him) told his Companions about when he (peace be upon him) was in Tabuk, stating the order in which they would happen. He (peace be upon him) said to Auf ibn Malik (may Allah be pleased with him), Count six signs that indicate the approach of the Hour: my death, next the liberation of Jerusalem, followed by a plague that will afflict you (and kill you in great numbers) as the plague that afflicts sheep, the increase of wealth to such an extent that even if one is given one hundred Dinars, he will not be satisfied, and then an affliction which no Arab house will escape. Finally, a truce between you and Bani Al-Asfar (i.e. the Romans) who will betray you and attack you under eighty flags, under each flag will be twelve thousand soldiers related by Al-Bukhari In this hadith the Prophet (peace be upon him) mentioned six matters, stating their order as being: First, his death, then the liberation of Jerusalem, which actually happened in 15 AH, followed by a great plague that killed many Companions, which happened in 18 AH when the Amwas plague afflicted the Muslims. After this, he (peace be upon him) said there would be an increase of wealth due to the liberation of many countries during the reign of Uthman, and then a trial that would afflict the Arabs, which happened during the sedition when Uthman (may Allah be pleased with him) was killed and which started a great affliction which no house escaped. Finally, he mentioned a truce between the Arabs and Bani Al-Asfar (the Romans), which is one of the signs of the Resurrection Day about which the Prophet (peace be upon him) told us.
The Prophet (peace be upon him) informed the Companions about the martyrdom of ‘Umar, Uthman, Ali, Talha and Zubair (may Allah be pleased with all of them), and that they would die as martyrs, not dying on their beds or dying in any other way which people die. The Prophet (peace be upon him) mentioned this fact when he (peace be upon him) climbed up the mountain of Hira; Abu Bakr, Umar, Uthman, Ali, Talha and Zubair were with him, and the mountain stirred, so the Prophet (peace be upon him) said, Be calm (O Hira)! There is no one on you but a Prophet, a man of truth, and martyrs related by Muslim All of them, except the Prophet (peace be upon him) and Abu Bakr (the man of truth, may Allah be pleased with him), died as martyrs.