Prayer: Doubts That Invalidate Prayers
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1151
The following are doubts that invalidate prayers:
1. A doubt about the number of rakʿahs performed in obligatory prayers consisting of two rakʿahs, such as ṣubḥ prayers and the prayer of a traveller. However, a doubt about the number of rakʿahs performed in recommended prayers and ṣalāt al‑iḥtiyāṭ does not invalidate them;
2. A doubt about the number of rakʿahs performed in prayers consisting of three rakʿahs;
3. A doubt about whether one has performed one rakʿah or more in a prayer consisting of four rakʿahs;
4. In a prayer consisting of four rakʿahs, before going into the second sajdah, one doubts whether he has performed two rakʿahs or more;
5. A doubt about whether one has performed two or five rakʿahs, or, two or more than five rakʿahs;
6. A doubt about whether one has performed three or six rakʿahs, or, three or more than six rakʿahs;
7. A doubt about the number of rakʿahs when one does not know at all how many rakʿahs he has performed;
8. A doubt about whether one has performed four or six rakʿahs, or four or more than six rakʿahs, as per the details that will be mentioned later.