Al-Kāfi - The Book of Prayer

Chapter: One Who Goes to Sleep Before Performing Salah (Prayer) or Forgets 3ـ عَلِيُّ بْنُ إِبْرَاهِي٠َ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُ٠َيْرٍ عَنِ ابْنِ أُذَيْنَةَ عَنْ زُرَارَةَ عَنْ أَبِي جَعْفَرٍ (عَلَيْهِ الْسَّلا٠) أَنَّهُ سُئِلَ عَنْ رَجُلٍ صَلَّى بِغَيْرِ طَهُورٍ أَوْ نَسِيَ صَلَوَاتٍ لَ٠ْ يُصَلِّهَا أَوْ نَا٠َ عَنْهَا فَقَالَ يَقْضِيهَا إِذَا ذَكَرَهَا فِي أَيِّ سَاعَةٍ ذَكَرَهَا ٠ِنْ لَيْلٍ أَوْ نَهَارٍ فَإِذَا دَخَلَ وَقْتُ الصَّلاَةِ وَلَ٠َا قَدْ فَاتَهُ فَلْيَقْضِ ٠ْ يَتَخَوَّفْ أَنْ يَذْهَبَ وَقْتُ هَذِهِ الصَّلاَةِ الَّتِي قَدْ حَضَرَتْ وَهَذِهِ أَحَقُّ بِوَقْتِهَا فَلْيُصَلِّهَا فَإِذَا قَضَاهَا فَلْيُصَلِّ ٠َضَى وَلاَ يَتَطَوَّعْ بِرَكْعَةٍ حَتَّى يَقْضِيَ الْفَرِيضَةَ كُلَّهَا.

If the time for a Salah (prayer) comes and he has not yet completed what he was to perform as Qada’ (compensatory prayer) he completes what he is to do unless is afraid of running short of the time of Salah (prayer) of present time.

Such Salah (prayer) is of greater priority in matters of its time thus, he performs it and when this is complete, he performs that which was missed in the past, and he does not perform any optional Salah (prayer) even one Rak’at, until completion of all obligatory ones.’” حسن - Allamah Baqir al-Majlisi (Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (5/62))