Chapter 40: Mubahalah
From a place called Najran a group of Christians came to debate with Prophet (SAW) about what Islam says about Jesus.
Christians believed Jesus (Isa (AS)) was divine.
Allah revealed to Prophet (SAW) in the Quran that Isa (AS) was human just like Adam (AS) was. Adam was created without both mother and father, from dust.
Adam was not divine. Allah can create life from nothing.
Isa (AS) was born without father. Allah can create life as he wills.
Christians debated - until Prophet (SAW) said let us do Mubahalah
Christians would select a group from them and Prophet (SAW) would choose a group from his side.
Prophet (SAW) said his group would include Fatima (RA), Ali (RA), Hasan and Husain (RA).
In Mubahalah you called for Allah's punishment to fall on the group that is lying.
Christians did not take the challenge, and instead asked for a treaty with the Muslims.
It is reported, later on - the two leaders of the Christians returned and accepted Islam.