Incident of H.Ali (a.s.) and a Jew

Declared Aba Abdillah Imam Ja'far ibn Mohammad al-Sadiq (a.s.):
"When Abu Bakr died and Umar took over, he returned to the mosque and sat down. A man came to him and said, "O Commander of the Faithful! I am one of the Jews. I am one of their scientists. I have several questions to ask you. If you answer them I will become a Muslim."
Umar said, "What are those questions?" He said, "Three, three and one. If you are ready I will ask them, but if there is someone more knowledgeable than you in your tribe direct me to him."
Then Umar said, "Go to that young man - that is Ali ibn Abi Talib (s)."

The man asked him (s) his questions. Ali (s) said, "Why did you say three, three and one? Why didn't you say seven?"
The Jew said, "Since then I would be ignorant. Should you not answer the first three, I will suffice and not ask the rest."

Ali (s) said, "Will you become a Muslim if I answer the first three questions?" The man said, "Yes." Then Ali (s) said, "Ask."
He said, "I want to ask you about the first stone placed on the Earth, the first spring gushed forth and the first tree grown."
Ali (s) said, "O Jew! You say that the first stone place on the Earth is the one in the Holy House of Bayt ul-Maqdis. But you lie. It is the stone that Adam brought down to Earth from Heaven." He said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

Ali (s) said, "You say that the first spring which gushed forth from the Earth was the one in the Holy House of Bayt ul-Maqdis. But you lie! It is the Spring of Life in which Yush'a ibn Noon washed that fish. It is the same spring from which al-Khizr drank. Whoever drinks from it will live forever." The Jew said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

Ali (s) added, "You say that the first tree grown on the Earth was an olive tree. But you lie! That tree was al-Ajwa which Adam brought down with him to the Earth from Heaven." He said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

The Jew said, "And now for the second three. How many Divine Leaders does this nation have to guide them who will not lose anything if all the people stop following them?" Ali (s) said, "Twelve Divine Leaders!" The Jew said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

The Jew asked, "Where does your Prophet reside in Paradise?" Ali (s) said, "In the highmost place and the noblest location in the Eternal Paradise." The Jew said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

The Jew asked, "Who are the people who live with him in the same house?" Ali (s) said, "The twelve Divine Leaders." The Jew said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

Then the Jew said, "And now for the seventh question. For how many years will his successor live after him?" Ali (s) said, "For thirty years." The Jew asked, "What will happen next? Will he die or will he get killed?" Ali (s) said, "He will be killed. He will be struck on the crown of his head with a sword and his beard will be covered with blood." The Jew said, "You are right! By God, Aaron wrote this down which was dictated to him by Moses (s)."

Reference:
Uyun Akhbar Al-Reza, Volume 1, Tradition 6-19