Q: An individual arrives at a masjid when the congregational prayer is in its second rak‘ah. Due to his ignorance of Islamic rules, he does not perform the tashahhud obligatory for him in the following rak‘ah. Is his prayer correct or not?
A: The prayer is correct but he should, by obligatory caution, perform the qaḍā’ of tashahhud. He should also perform the two prostrations of inadvertence as he failed to perform the tashahhud.