Sunnah prayer when combining prayers
2-1-2018 | IslamWeb
Question:
Assalaamu alaykum wa rahmatullaahi wa barakaatuhu, Shaykhs. If a person is combining the Maghrib and ‘Ishaa’ prayers at the time of the Maghrib, can that person pray the Sunnah of the ‘Ishaa’ prayer after its time begins, or must it also be prayed at the Maghrib time itself and it can thus not be delayed? And, please, also give advice for someone who is combining the Thuhr and the ‘Asr; should the Sunnah prayers of the Thuhr that are prayed before it be prayed after the Sunnah prayer that is prayed after it, or should they be prayed in their correct sequence, the first ones first and the latter ones later? May Allah reward you, Shaykhs.
Answer:
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
If a person combines the Maghrib and the ‘Ishaa’ prayers at the time of the Maghrib, then he should – after praying the Maghrib and the ‘Ishaa’ – perform the Sunnah of the Maghrib, then the Sunnah of the ‘Ishaa’, and then the Witr.
If he combines the Thuhr and ‘Asr prayers, then he should perform the pre-Sunnah of the Thuhr before performing the two combined prayers, then perform the two combined prayers (the Thuhr and ‘Asr), then the post-Sunnah of the Thuhr, and then the pre-Sunnah of the ‘Asr. This is the manner of performing the Sunnah prayers in this situation according to some of the researching scholars. An-Nawawi 
wrote:
“Ar-Raafi‘i said that when combining the Thuhr and the ‘Asr, the worshiper should perform the Sunnah of the Thuhr, then the Sunnah of the ‘Asr, and then the two combined prayers (the Thuhr and ‘Asr). When combining the Maghrib and the ‘Ishaa’, he should perform the two combined prayers, then the Sunnah of the Maghrib, then the Sunnah of the ‘Ishaa’, and then the Witr. I say: what Imaam Ar-Raafi‘i said regarding the Maghrib and the ‘Ishaa’ is correct; however, his view regarding the Thuhr and the ‘Asr is odd and weak. The correct view according to the researching scholars is to perform the prayers in the following order: the pre-Sunnah of the Thuhr, the Thuhr, the ‘Asr, the post-Sunnah of the Thuhr, and then the pre-Sunnah of the ‘Asr. How could performing the post-Sunnah of the Thuhr be valid if it is performed before performing the Thuhr itself? And we have previously underlined that its time becomes due after performing the Thuhr. Likewise is the pre-Sunnah of the ‘Asr; it becomes due when the time of the ‘Asr starts. The time of the ‘Asr, when combining the Thuhr and the ‘Asr, starts after performing the Thuhr prayer.” [Rawdhat At-Taalibeen]
Allah knows best.