Leading maghrib with a long recitation and fajr and ‘isha’ with a short one

Question

What is the ruling on reciting a ruku‘ (a section of the Qur’an) in the maghrib prayer, and suras in ‘isha’ and fajr? Is the prayer valid this way? The imam deliberately recites Surat al-Shams in the first rak‘a of ‘isha’ every day for a week in a row, while in both rak‘as the ruku‘ was not complete; and sometimes he also does this: in the first rak‘a he began a ruku‘, recited a little and completed the rak‘a, then in the second rak‘a he began another ruku‘ and did not complete that one either.

Answer

In this way everyone’s prayer will be discharged; the objection against the imam is wrong. What is better (awla) is that a separate (independent) sura be recited in each rak‘a. In fajr and zuhr — the long suras of the mufassal; in ‘asr and ‘isha’ — the medium suras of the mufassal (from Surat al-Buruj to Surat Lam yakun)

Source: Fatawa Mahmudiyya

Preview. The full text opens with JavaScript enabled.