Sahih
Muslim
صحيح مسلم
06
The Book of Prayer - Travellers
كتاب صلاة المسافرين وقصرها
Chapter 9: It is disliked to start a voluntary prayer after the Mu’adhdhin has started to say Iqamah for prayer, whether that is a regular sunnah, such as the sunnah of Subh or Zuhr, or anything else, and regardless of whether he knows that he will catch up with the rak`ah with the Imam or not
باب كَرَاهَةِ الشُّرُوعِ فِي نَافِلَةٍ بَعْدَ شُرُوعِ الْمُؤَذِّنِ
Sahih Muslim 711 b
Ibn Buhaina reported
The dawn prayer had commenced when the Messen- ger of Allah ﷺ a person observing prayer, whereas the Mu'adhdhin had pronounced the Iqama. Upon this he (the Holy Prophet ) remarked: Do you say four (rak'ahs) of Fard in the dawn prayer?حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ سَعْدِ بْنِ إِبْرَاهِيمَ، عَنْ حَفْصِ بْنِ عَاصِمٍ، عَنِ ابْنِ بُحَيْنَةَ، قَالَ أُقِيمَتْ صَلاَةُ الصُّبْحِ فَرَأَى رَسُولُ اللَّهِ صلى الله عليه وسلم رَجُلاً يُصَلِّي وَالْمُؤَذِّنُ يُقِيمُ فَقَالَ " أَتُصَلِّي الصُّبْحَ أَرْبَعًا " .
Grade: Sahih