Imam Reza(AS),had foretold many events before they happened, and they happened just as he had predicted. These prophecies clearly confirm the original faith of the Shï'a who say that Allah, the Exalted, endowed the Holy Infallible Imams of the Household (of the Holy Prophet) with excellence and inner knowledge, just as He had endowed His messengers.
The following are some of the Imam's prophecies:
1. Al-Hasan b. Bashshar narrated on the authority of Imam Reza(AS), who said: "'Abd Allah (i.e. al-Ma'mun) will kill Mohammed (i.e. al-Amïn)." I (al-Hasan b. Bashshar) asked him: "Will 'Abd Allah b. Harun kill Mohammed b. Harun?" "Yes," he replied, "'Abd Allah who is in Khurasan will kill Mohammed b. Zubayda who is in Baghdad." Then he recited this poetry line
Surely successive spites expose you and bring out the hidden malady.
Some days ago and al-Ma'mun killed his brother al-Amïn.
2. Another example of the Imam's inner knowledge is that when Mohammed b. Ima`m al-Sa`diq rose in Mecca and summoned the people to himself and broke the pledge of allegiance to al-Ma'mun, Imam Reza` went to him and said to him: "O Uncle, do not accuse your father or your brother ( i.e. Imam al-Ka`zim, peace be on him) of lying, for this authority will not go well with you." However, Mohammed b. Ima`m al-Sa`diq paid no attention to the Imam's advice, and he announced his revolt against al-Ma'mun. Shortly after that, the troops of al-M'mun headed by al-Jalu`di attacked Mohammed and his fighters and defeated them. Then Mohammed asked al-Jalu`di for security, and he gave it to him. Then he went up on the pulpit and abdicated authority, saying: "This authority belongs to al-M'mun and I have no right in it. "
3. Al-Husayn, the son of Imam Musa, peace be on him, has said: "We were youths from the Banu Hashim. While we were sitting around al-Reza, peace be on him, Ja'far b. 'Umar al-'Alawi passed by us shabby. We looked at each other and laughed at him, so al-Reza said: 'In the near future he (Ja'far b. 'Umar al-'Alawi) will have a lot of money and many followers.' A month ago, Ja'far became the governor of Medina and enjoyed good conditions. "
4. Muhawil al-Sijistani has narrated: "When Imam Reza, peace be on him, was commanded to go to Khurasan, I was in Medina. Al-Reza(AS) entered the mosque in order to say farewell to Allah's Messenger, may Allah bless him and his family. He said farewell to him several times. Throughout this (time) he went and came back to the grave. He wept and wailed aloud, so I walked towards him and greeted him, and he greeted me. I congratulated him, and he said to me: 'Leave me, for I am going to go out of the neighborhood of my grandfather; I will die in exile, and be buried beside Harun.' I went out to follow him on the road until he arrived in Khurasan. He stayed in it for a time, and then he was buried by Harun. "
The matter was just as the Imam had predicted. He went to Khurasan, and did not return from it. He was assassinated by al-M'mun, the 'Abbasid Caliph, and was buried beside Ha`run al-Rashïd.
5. Safwan b. Yahya has reported: " When Abu Ibrahïm (i.e. Imam al-Kazim) passed away and Abul-Hasan al-Reza, peace be on him, spoke (i.e. undertook the office of the Imamate), we were afraid for him. He was told: 'You have made public a great matter and on account of that, we fear for you from this tyrant (i.e. Harun al-Rashïd).' 'Let him try as hard as he can,' he answered, 'he will find no way to harm me. "
The matter happened as he had predicted. Harun al-Rashïd did not mistreat him. The Imam underlined this meaning to his companions. Mohammed b. Sinan has reported: "I (i.e. Mohammed b. Sina`n) said to Abul-Hasan al-Reza(AS) during the days of Harun: 'Surely, you have made yourself famous through this matter and your sitting in the assembly of your father, while the sword of Harun is dripping blood (i.e. the blood of the Household of the Prophet and their followers). He, peace be on him, said: 'Allah's Messenger (may Allah bless him and his family) has encouraged me when he said: 'If Abu Jahl takes a hair from my head, then bear witness that I am not a prophet.' For this reason I say to you: 'If Harun (al-Rashïd) takes a hair from my head, then bear witness that I am not an Imam.'
Several times the Imam , peace be on him, announced that Harun would not mistreat him, and that he would be buried beside him. Hamza b. Ja'far al-Larijani has narrated: "Harun went out of the gate of the Sacred Mosque, and 'Imam Reza(AS) went out of the gate and said: 'How remote the abode is! And how near the meeting is! Surely, Tus will gather me and him together! '
The Imam has stressed his burial beside Harun in many traditions. Musa b. Harun has narrated: "While Harun al-Rashïd was delivering a speech in the Mosque of Medina, I saw 'Ali (al-Reza(AS)), and he said to me: 'You will see that I and he (Harun al-Rashïd) will be buried in one house.'
6. Another example of the Ima`m's inner knowledge is the calamity of the Bara`mika. Imam Reza(AS) left medina to make the pilgrimage in the year in which Harun al-Rashid,the then ruling Abbasid caliph made the pilgrimage. He came to a mountain called Fari on the left of the road. Abu al-Hasan al-Reza(AS), looked at the mountain and said:
"Fari, the one who destroys (a resting place in you) whill be cut limb from limb." We did not know what that meant.
When Harun reached that place he stopped there. Ja'far bin Yahya Barmaki the grand vizier of Harun al-Rashid went up the mountain and ordered a resting-place to be set up for him. On his return from Mecca, Ja'far bin Yahya Barmaki went back up the hill and ordered it to be destroyed.But as soon as when he got to Iraq Ja'far bin Yahya Barmaki was cut limb from limb by the orders of Harun al-Rashid in the palace coup staged by the caliph against the Barmaki family.
7. Mohammed b. 'Isa has reported on the authority of Habïb al-Naba`ji, who said: "I saw Allah's Apostle, may Allah bless him and his family, in a vision. He came to al-Nabaji and stopped at the mosque where the pilgrims stopped every year. I went to him and greeted him. There was before him a tray made of palm leaves, and there was Sayhani dates in the tray. He gave me a handful of these dates.
I counted them and they were eighteen. I asked (a person) to explain the vision, and he told me that I would live for eighteen years. Twenty days ago, while I was on my farm, a person came and told me about the coming of Imam Reza(AS) from Medina and his stopping at that mosque. I saw the people going to him, so I went to him. I saw him sitting in the place where Allah's Apostle, may Allah bless him and his family, sat in the vision.
There was before him a tray made of palm leaves, and there was Sayhani dates in it. I greeted him, and he, peace be on him, greeted me. He asked me to come nearer to him and gave me a handful of these dates. I counted them and they were equal to those which Allah's Apostle, may Allah bless him and his family, had given to me. As a result I said: 'Increase me, O Son of Allah's Apostle!' He said: 'If Allah's Apostle, may Allah bless him and his family, increased you, we would increase you."
8. Ja'far b. Sa`lih has narrated: "I came to Imam Reza(AS) and said to him: 'My wife is pregnant, so supplicate Allah to make her give birth to a male.' As a result he said: 'They are twin.' I went away and said: 'I will name one of them Mohammed and the other 'Ali.' Then I came to him, and he said to me: 'Name one of them 'Ali and the other Umm 'Amru`.' When I went to Kufa, my wife had given birth to a male and a female, so I named the male 'Ali and the female Umm 'Amru."
source : sibtayn