Sahih al-Bukhari 576
Book 9: Times of the Prayers · Narrated by Qatada
Arabic
حَدَّثَنَا حَسَنُ بْنُ صَبَّاحٍ، سَمِعَ رَوْحًا، حَدَّثَنَا سَعِيدٌ، عَنْ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ نَبِيَّ اللَّهِ صلى الله عليه وسلم وَزَيْدَ بْنَ ثَابِتٍ تَسَحَّرَا، فَلَمَّا فَرَغَا مِنْ سَحُورِهِمَا قَامَ نَبِيُّ اللَّهِ صلى الله عليه وسلم إِلَى الصَّلاَةِ فَصَلَّى. قُلْنَا لأَنَسٍ كَمْ كَانَ بَيْنَ فَرَاغِهِمَا مِنْ سَحُورِهِمَا وَدُخُولِهِمَا فِي الصَّلاَةِ قَالَ قَدْرُ مَا يَقْرَأُ الرَّجُلُ خَمْسِينَ آيَةً.
English translation
Narrated Qatada:Anas bin Malik said, "The Prophet (ﷺ) and Zaid bin Thabit took the 'Suhur' together and after finishing the meal, the Prophet (ﷺ) stood up and prayed (Fajr prayer)." I asked Anas, "How long was the interval between finishing their 'Suhur' and starting the prayer?" He replied, "The interval between the two was just sufficient to recite fifty 'Ayat." (Verses of the Qur'an)
Reference: Sahih al-Bukhari 576, Book of Times of the Prayers. English translation by Dr. Muhammad Muhsin Khan.