Long ago in Arabia, there was to be a debate between the holy prophe tof Islam Mohammad (PBUH) and Christians of Najran.
During the event each side was to condemn the liar, asking God for punishment. However, when the Christian delegation saw the immaculate faces of the Prophet (PBUH) and his family (Ahlul Bait) including Imam Ali, holy Lady Fatima Zahra, Imam Hassan, and Imam Hussain (peace be upon them), they were astonished; thus, they refrained from seeking condemnation towards the prophet and his household (peace be upon them).
They knew that the prophet’s dua and his family’s Duas (PBUT) would be accepted, so the Bishop of Najran asked the prophet (PBUH) for forgiveness and compromise.
This event has been related in both Sunni and Shi’i books of hadith and Qur’anic exegesis (tafsir).
It is related in the al-Tafsir of al-Tha’labi:
When the Prophet (S) called the Christians for the imprecation they said: 'Let us return and think over it.' When they were alone, they asked al-'Aqib - and he was a man of good judgment among them: 'O 'Abd al-Masih! What is your opinion? , He said: ' By Allah! You are well-aware, O Christians, that Muhammad is a prophet sent by Allah, and that he has brought to you the decisive word about your Companion ('Isa).
By Allah! Whenever a nation has entered into imprecation with a prophet, their elders have perished and their youngsters have died. And if you do it, we shall surely perish; but, if you turn down, for the love of your religion and (want) to remain on what you have at present, then make peace with the man and go back to your towns.
"So they came to the Messenger of Allah; and he had come out in the morning carrying al-Husayn in his lap, holding the hand of al-Hasan, with Fatimah walking behind him and 'Ali was behind her; and he was saying: 'When I pray, you say "Amen" '. Then the Bishop of Najran said: 'O Christians! Surely I see the faces that if they ask Allah to remove a mountain from its place, He would surely remove it. Therefore, do not do imprecation, otherwise you will perish, and there will not remain any Christian on the face of the earth, upto the Day of Resurrection’.
"Then they said: 'O Abu'l-Qasim! We have decided that we should not enter into imprecation against you; and that we leave you on your religion and we remain on our religion.'
He said: 'Well, if you refuse imprecation, then accept Islam - you will have (the rights) which (other) Muslims have, and on you shall be (the duties) which are on them.' But they refused. So (the Prophet) said: 'Then I shall fight you.' They said: 'We do not have strength to fight against the Arabs. But we shall make peace with you that you will not fight against us or frighten us; nor will you turn us away from our religion, on the condition that we shall pay to you every year two thousand robes - one thousand in Safar and one thousand in Rajab and thirty coats of mail, (of) common (quality), made of iron.'
So the Prophet made agreement with them on these conditions. And he said, 'By Him in Whose hand is my soul! Surely destruction had almost descended on the people of Najran. And if they had entered into imprecation they would have been transformed into monkeys and pigs, and there would have erupted in the valley a conflagration of fire engulfing them all; and surely Allah would have annihilated Najran and its inhabitants - even the birds on tree tops; and the year would not have ended for all the Christians but they would have perished.’
In the Name of Allah, the Most Compassionate, the Most Merciful.
O Allah! Send your blessings to the chief of Your Messengers and the Last of Your Prophets, Muhammad (S), and his pure and cleansed progeny.
Should anyone argue with you concerning him, after the knowledge that has come to you, then say: ‘Come! Let us call our sons and your sons, our women and your women, our souls and your souls, then let us pray earnestly and call down Allah’s curse upon the liars’. (Qur'an 3:61)
This verse refers to the famous event of 'al-Mubahala ' which took place in the year 10 A.H between the Prophet (S) and the Christians of Najran and which is mentioned in all well-known books of traditions, tafsir (exegesis) and history by Muslim scholars.
Najran was a fertile land located in the northern mountainous region of Yemen about 20 Km from Sana’a. About 40,000 Christians inhabited the land divided into 73 small towns.
They were idol worshipers historically just like the Arabs, but a priest named Phemion (Faymiyun), a builder by profession, preached Christianity in the area of Najran and soon all the population converted to Christianity and Najran became a important center for the Christians.
They also constructed a church and named it 'Ka’ba-e-The debate was traditionally known as Mubahala, which occurred on the 10th year of AH. The prophet (PBUH) decided to participate in Mubahala and took up an invitation to meet with the Christians.'. They prayed and offered various offerings there which resulted in an annual income of about two hundred thousand Dinars which was used for the priest who lived and studied there.
After the conquest of Makkah, when Islam started spreading rapidly and the warring groups came under the flag of Islam, the Holy Prophet (PBUH) started sending emissaries to the tribes who had not yet accepted Islam. In 10 A.H. a similar message was sent to the Christians of Najran and they were offered either to accept the teachings of Islam or live in the protection of Muslims and pay the Jizya tax.
The Prophet of Islam (PBUH) had written a letter to Abu al-Harith ibn ‘Alqama, the Grand Bishop of Najran, who was the official representative of the Roman Church in the Hijaz and invited the people of that area to embrace Islam.