Prayer: Making the Intention to Perform Prayer on One's Own After the Imam's Recitation
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1404
If after the imam has recited Sūrat al-Ḥamd and the other surah a follower makes the intention to perform the prayer on his own due to a legitimate excuse, it is not necessary that he recite Sūrat al-Ḥamd and the other surah. However, if he does not have a legitimate excuse or he makes the intention of performing the prayer on his own before the completion of Sūrat al-Ḥamd and the other surah, then based on obligatory precaution, it is necessary that he recite all of Sūrat al-Ḥamd and the other surah.