What is the ruling regarding two men praying together when one suspects he passed wind or made a sound, and the other denies it, leading each to believe the other's prayer is invalid?
Chapter on Praying with Impurity and Other Matters
Al-Mughni
Book of Prayer
Primary text
If two men are praying in congregation and each suspects the other of breaking ablution (wudu) but denies it, they must both perform ablution and then pray. This ruling is based on the narration where the invalidity of one partner's prayer invalidates the other's due to the subsequent status of praying alone (fard). Alternatively, upon the preferred narration, each intends to become an individual praying alone and completes their prayer as such. A third possibility suggests the prayers are only invalidated if they complete them without changing their intention, as the follower believes he is following someone who broke ablution, and the Imam believes he is leading someone whose ablution is broken.
Supporting text
The ruling to perform ablution may be intended by Imam Ahmad (may Allah have mercy on him) so that they can correctly perform the congregational prayer afterward, as neither can validly follow or lead the other while suspecting a break in ablution. This command for ablution might be for precaution. If they pray individually, ablution is not obligatory upon either, because certainty of purity exists in both, while impurity is doubtful, and certainty is not overturned by doubt.