What is the ruling on an individual praying alone behind a standing congregation due to a dispute between him and one of the worshippers?

If a person did not join the congregational prayer and prayed alone, this is not appropriate for him. His prayer is disliked, but it is valid. However, if he joined the congregation and then broke his prayer upon seeing a specific person, he is not permitted to interrupt an obligatory prayer without a legitimate Shar'i excuse. He is considered sinful and must repent, because interrupting an obligatory act of worship without a Shar'i justification is impermissible by the consensus of jurists. Disagreement among Muslims does not permit interrupting an obligatory prayer; rather, it is among the matters that corrupt one's religion.