“We ate Suhur with the Messenger of Allah ﷺ then we got up to perform prayer.” I said: “How long was there between the two?” He said: “As long as it takes to recite fifty verses.” (Using translation from Ibn Mājah 1694)   

«تَسَحَّرْنَا مَعَ رَسُولِ اللَّهِ ﷺ» قَالَ «ثُمَّ قَامَ إِلَى الصَّلَاةِ» قَالَ قُلْتُ كَمْ كَانَ بَيْنَ الْأَذَانِ وَبَيْنَ السُّحُورِ؟ قَالَ «قَدْرُ قِرَاءَةِ خَمْسِينَ آيَةً»