holy Prophets (sawa) debate with the Christians of Najaran

The Prophet: I invite you to the religion of monotheism and the worship of One Allah and submission to His commands. (Then he recited some verses of the Holy Qur'an before, them).
The representatives of Najran: If Islam means faith in the only Lord of the World we already believe in Him and act according to His Commands.
The Prophet: Islam carries a few signs and some of your actions show that you do not believe in Islam. How do you say that you worship One Allah when you worship the cross and do not abstain from the meat of the swine and believe that Allah has son?
Representatives: We believe him (i.e. 'Isa) to be God because he brought the dead to life, cured the sick, made a bird with clay and made it fly, and all these things show that he is God.
The Prophet: No. He is the servant of Allah and is His creature. Allah placed him in the womb of Mary. And all this power and strength was given to him by Allah.
One of the represenatatives: Yes! He is the son of God, because Mary gave him birth without marrying anyone, and it is, therefore, necessary that his father should be the very Lord of the World.
At this juncture the Archangel Jibreel came and advised the Prophet to tell them: "From this point of view the condition of 'Isa resembles that of Adam who was created by Allah with His unlimited power from clay without his having a father and a mother7 and if one's not having a father is the proof of one's being the son of Allah, Adam is all the more entitled to this position, because he had neither a father nor a mother".
The representatives: Your words do not satisfy us. The best way to resolve the issue is that we should engage in imprecation with each other at an appointed time and may curse the liar and pray to Allah that He may destroy the liar.8
At this moment the Archangel Jibreel came and brought the verse pertaining to imprecation and conveyed to the Prophet the Divine command that he should engage in imprecation with those, who contended and disputed with him and both the parties should pray to Allah that He might deprive the liar of His blessings. The Holy Qur'an says,
If anyone disputes with you after the knowledge has come to you, say, 'Let each of us bring our children, our women, our people and ourselves to one place and pray to Allah to curse upon the liars among us'.(Surah Ale Imran, 3:62)
Both the parties agreed to settle the issue through imprecation and it was decided that all of them would be ready for it on the following day.