Arabic (Original)
حَدَّثَنَا حُسَيْنُ بْنُ مُحَمَّدٍ حَدَّثَنَا أَيُّوبُ بْنُ جَابِرٍ عَنْ عَبْدِ اللَّهِ بْنِ عِصْمَةَ الْحَنَفِيِّ عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ قَالَ صَلَّى رَجُلٌ خَلْفَ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَجَعَلَ يَرْكَعُ قَبْلَ أَنْ يَرْكَعَ وَيَرْفَعُ قَبْلَ أَنْ يَرْفَعَ فَلَمَّا قَضَى النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ الصَّلَاةَ قَالَ مَنْ فَعَلَ هَذَا قَالَ أَنَا يَا رَسُولَ اللَّهِ أَحْبَبْتُ أَنْ أَعْلَمَ تَعْلَمُ ذَلِكَ أَمْ لَا فَقَالَ اتَّقُوا خِدَاجَ الصَّلَاةِ إِذَا رَكَعَ الْإِمَامُ فَارْكَعُوا وَإِذَا رَفَعَ فَارْفَعُوا.
English Translation
Husayn ibn Muhammad narrated to us, Ayyub ibn Jabir narrated to us, from Abdullah ibn Ismah al-Hanafi, from Abu Sa'id al-Khudri, who said: A man prayed behind the Prophet, peace and blessings be upon him, and began to bow before he bowed, and rise before he rose. When the Prophet, peace and blessings be upon him, finished the prayer, he said: "Who did this?" The man said: "I did, O Messenger of Allah. I wanted to know whether you were aware of it or not." He said: "Beware of making the prayer deficient. When the imam bows, then bow, and when he rises, then rise."