1187. If after completing the salÁm of prayer, a person doubts whether he offered his prayer correctly or not—such as doubting whether he had performed rukÙ‘ or not—or doubts whether he had offered four rak‘ah or five, he should dismiss his doubt. A great number of renowned scholars have said that if both possibilities entertained in the doubt are invalid, his prayer will be invalid. An example of this is a person who doubts after completing the salÁm of a four rak‘ah prayer, whether he offered three or five rak‘ah. However, this ruling is problematic and obligatory precaution dictates that he should perform another rak‘ah, perform two sajdah al-sahw after salÁm, and also repeat his prayer.