Chapter on the Rulings on Forgetfulness (Ahkam al-Sahw)
Tahdhīb al-Aḥkām|Volume 2|Book 1|Chapter 16
مُحَمَّدُ بْنُ أَحْمَدَ بْنِ يَحْيَى عَنْ أَحْمَدَ بْنِ اَلْحَسَنِ عَنْ عَمْرِو بْنِ سَعِيدٍ عَنْ مُصَدِّقِ بْنِ صَدَقَةَ عَنْ عَمَّارِ بْنِ مُوسَى اَلسَّابَاطِيِّ عَنْ أَبِي عَبْدِ اَللَّهِ عَلَيْهِ اَلسَّلاَمُ: فِي اَلرَّجُلِ يُرِيدُ أَنْ يُصَلِّيَ ثَمَانِيَ رَكَعَاتٍ فَيُصَلِّي عَشْرَ رَكَعَاتٍ أَيَحْتَسِبُ بِالرَّكْعَتَيْنِ مِنْ صَلاَةٍ عَلَيْهِ قَالَ« لاَ إِلاَّ أَنْ يُصَلِّيَهَا عَمْداً فَإِنْ لَمْ يَنْوِ ذَلِكَ فَلاَ»
Muhammad ibn Ahmad ibn Yahya from Ahmad ibn al-Hasan from ‘Amr ibn Sa‘id from Musaddiq ibn Sadaqah from ‘Ammar ibn Musa al-Sabati:
Abu Abdillah عليه السلام, peace be upon him, (was asked) regarding a man who intends to pray eight rak‘ahs but ends up praying ten rak‘ahs, are the two extra rak‘ahs counted as part of another prayer upon him? Imam عليه السلام said: "No, unless he deliberately intends that. But if he did not intend it, then no."
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 369
- Ṣaḥīḥ al-Tahdhīb