Mubahala, or The Islamic Cursing Contest

S 3:61 So he who argues with you {singular pronominal suffix} about it after what has come to you of knowledge, say: Come, let us call our sons and your sons and our women and your women and ourselves and yourselves then let us execrate and put the curse of Allah on the liars.

Disputants are to call their sons, their women and themselves? Does one call himself? Was Allah's curse to fall on the women and children? Did the founder of Islam bring his sons?

Asbab al-Nuzul for this verse:

(… say (unto him): Come! We will summon our sons and your sons…) [3:61]. Abu Sa‘d informed us> ‘Abd al-Rahman ibn Muhammad al-Zimjari> Ahmad ibn Ja‘far ibn Malik> ‘Abd Allah ibn Ahmad ibn Hanbal> his father> Husayn> Hammad ibn Salamah> Yunus> al-Hasan who said: “The two monks of Najran came to see the Prophet, Allah bless him and give him peace, and he invited them to surrender to Allah. One of them said: ‘We have surrendered to Allah before you’. He said: ‘You lie! Three things prevent you from surrendering to Allah: your prostration before the cross, your claim that Allah has a son and your consumption of wine’. They said: ‘What do you say about Jesus?’ The Prophet, Allah bless him and give him peace, did not answer. But then this verse was revealed (This (which) We recite unto thee is a revelation and a wise reminder… Lo! the likeness of Jesus with Allah is as the likeness of Adam) up to Allah’s saying (… say (unto him): Come! We will summon our sons and your sons…). Then the Messenger of Allah, Allah bless him and give him peace, challenged them to summon Allah’s curse upon the one who is lying amongst them (Mula‘anah). The Messenger of Allah, Allah bless him and give him peace, went and brought al-Hasan, al-Husayn, Fatimah and all his family and children, peace be upon them. When the two Christians left, one of them said to the other: ‘Consent to pay the Jizyah and do not agree to summon Allah’s curse on the liar’. They went back and said: ‘We agree to pay the Jizyah and abstain from summoning Allah’s curse on the liar’ ”. ‘Abd al-Rahman ibn al-Hasan al-Hafiz informed us among that which he gave us permission to narrate from him> Abu Hafs ‘Umar ibn Ahmad al-Wa‘iz> ‘Abd Allah ibn Sulayman ibn al-Ash‘ath> Yahya ibn Hatim al-‘Askari> Bishr ibn Mihran> Muhammad ibn Dinar> Dawud ibn Abi Hind> al-Sha‘bi> Jabir ibn ‘Abd Allah who said: “The delegation of the people of Najran came to see the prophet, Allah bless him and give him peace. The deputy chief and the master spoke with the Prophet and he invited them to surrender to Allah. They said: ‘We have surrendered to Him before you’. He said: ‘You lie! And if you wish I will inform you about that which prevents you from surrendering to Allah’. They said: ‘Do inform us!’ He said: ‘It is the love of the cross, the consumption of wine and pork’. Then he challenged them to summon Allah’s curse upon the liar amongst them. They promised to come and see him in the evening. The Messenger of Allah, Allah bless him and give him peace, went and brought Fatimah, al-Hasan and al-Husayn whose hands he held, then he sent for the two men. But they refused to come and see him and agreed to pay a levied tax. The Prophet, Allah bless him and give him peace, said then: ‘By Him Who has sent me with the truth, had they agreed to summon Allah’s curse on the liar, fire would have rained on the valley [where the delegation of Najran had camped]’. Then the following verse was revealed about them ((unto him): Come! We will summon our sons and your sons…)”. Al-Sha‘bi said: “our sons refer to al-Hasan and al-Husayn and our women refers to Fatimah, while ourselves refers to ‘Ali ibn Abi Talib, may Allah be well pleased with one and all”. Altafsir.com - The Tafsirs - التفاسير

Were the monks to bring their wives and sons? Al-Hasan and Al-Husayn, the founder's grandsons, were his sons? An adopted boy can't be considered a son but a grandson can? Fatimah, one woman, may be considered women? Ali was 'ourselves'?

Ibn Kathir says:

The reason for the call to Mubahalah and the revelation of the Ayat from the beginning of this Surah until here, is that a delegation from the Christians of Najran (in Yemen) came to Al-Madinah to argue about `Isa, claiming that he was divine and the son of Allah. Allah sent down the beginning of this Surah until here, to refute their claims, as Imam Muhammad bin Ishaq bin Yasar and other scholars stated.

Muhammad bin Ishaq bin Yasar said in his famous Sirah, "The delegation of Christians from Najran came to the Messenger of Allah. The delegation consisted of sixty horsemen, including fourteen of their chiefs who make decisions. These men were Al-`Aqib, also known as `Abdul-Masih, As-Sayyid, also known as Al-Ayham, Abu Harithah bin `Alqamah, of the family of Bakr bin Wa`il and Uways bin Al-Harith. They also included, Zayd, Qays, Yazid, Nabih, Khuwaylid, `Amr, Khalid, `Abdullah and Yuhannas. Three of these men were chiefs of this delegation, Al-`Aqib, their leader and to whom they referred for advice and decision; As-Sayyid, their scholar and leader in journeys and social gatherings; and Abu Harithah bin `Alqamah, their patriarch, priest and religious leader. Abu Harithah was an Arab man from the family of Bakr bin Wa`il, but when he embraced Christianity, the Romans and their kings honored him and built churches for him (or in his honor). They also supported him financially and gave him servants, because they knew how firm his faith in their religion was.'' Abu Harithah knew the description of the Messenger of Allah from what he read in earlier divine Books. However, his otherwise ignorance led him to insist on remaining a Christian, because he was honored and had a high position with the Christians. Ibn Ishaq said, "Muhammad bin Ja`far bin Az-Zubayr said that, `The (Najran) delegation came to the Messenger of Allah in Al-Madinah, entered his Masjid wearing robes and garments, after the Prophet had prayed the `Asr prayer. They accompanied a caravan of camels led by Bani Al-Harith bin Ka`b. The Companions of the Messenger of Allah who saw them said that they never saw a delegation like them after that... Then Abu Harithah bin `Alqamah and Al-`Aqib `Abdul-Masih or As-Sayyid Al-Ayham spoke to the Messenger of Allah, and they were Christians like the king (Roman King). However, they disagreed about `Isa; some of them said, `He is Allah,' while some said, `He is the son of Allah,' and some others said, `He is one of a trinity.' Allah is far from what they attribute to Him.''

Indeed, these are the creeds of the Christians. They claim that `Isa is God, since he brought the dead back to life, healed blindness, leprosy and various illnesses, told about matters of the future, created the shape of birds and blew life into them, bringing them to life. However, all these miracles occurred by Allah's leave, so that `Isa would be a sign from Allah for people.

They also claim that `Isa is the son of Allah, since he did not have a father and he spoke when he was in the cradle, a miracle which had not occurred by any among the Children of Adam before him, so they claim. They also claim that `Isa is one of a trinity, because Allah would say, `We did, command, create and demand.' They said, `If Allah were one, he would have said, `I did, command, create and decide.' This is why they claim that `Isa and Allah are one (Trinity). Allah is far from what they attribute to Him, and we should mention that the Qur'an refuted all these false Christian claims.

Ibn Ishaq continued, "When these Ayat came to the Messenger from Allah, thus judging between him and the People of the Book, Allah also commanded the Prophet to call them to the Mubahalah if they still refused the truth. The Prophet called them to the Mubahalah. They said, `O Abu Al-Qasim! Let us think about this matter and get back to you with our decision to what we want to do.' They left the Prophet and conferred with Al-`Aqib, to whom they referred to for advice. They said to him, `O `Abdul-Masih! What is your advice' He said, `By Allah, O Christian fellows! You know that Muhammad is a Messenger and that he brought you the final word regarding your fellow (`Isa). You also know that no Prophet conducted Mubahalah with any people, and the old persons among them remained safe and the young people grew up. Indeed, it will be the end of you if you do it. If you have already decided that you will remain in your religion and your creed regarding your fellow (`Isa), then conduct a treaty with the man (Muhammad) and go back to your land.' They came to the Prophet and said, `O Abu Al-Qasim! We decided that we cannot do Mubahalah with you and that you remain on your religion, while we remain on our religion. However, send with us a man from your Companions whom you are pleased with to judge between us regarding our monetary disputes, for you are acceptable to us in this regard.'''

Al-Bukhari recorded that Hudhayfah said, "Al-`Aqib and As-Sayyid, two leaders from Najran, came to the Messenger of Allah seeking to invoke Allah for curses (against whoever is unjust among them), and one of them said to the other, `Let us not do that. By Allah, if he were truly a Prophet and we invoke Allah for curses, we and our offspring shall never succeed afterwards.' So they said, `We will give you what you asked and send a trusted man with us, just a trusted man.' https://quranx.com/Tafsir/Kathir/3.59

When the founder of Islam was struggling, then it appears that he called for Mubahala. He later came up with S 3:7 See: Muhammad's attempt of damage control: How Sura 3:7 suddenly makes sense Can a disputant only be cursed by Allah if he calls upon it to do so? Some will say that the reason that the Najranis wouldn't call for a curse to be delivered was because they were in fact liars. But Christians are not in the habit of calling curses down on their fellow man.

Further reading: Mubahala: A Prayer-Duel With A Muslim