Full Sharh — Mishkat al-Masabih 958
وَعَن عبد لله بن بُحَيْنَة: أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ صَلَّى بِهِمُ الظُّهْرَ فَقَامَ فِي الرَّكْعَتَيْنِ الْأُولَيَيْنِ لَمْ يَجْلِسْ فَقَامَ النَّاسُ مَعَهُ حَتَّى إِذَا قَضَى الصَّلَاةَ وَانْتَظَرَ النَّاسُ تَسْلِيمَهُ كَبَّرَ وَهُوَ جَالِسٌ فَسَجَدَ سَجْدَتَيْنِ قَبْلَ أَنْ يُسَلِّمَ ثُمَّ سَلَّمَ
English Translation
‘Abdallah ibn Buhaina said that the Prophet led them in the noon prayer, and when he stood up at the end of the first two rak'as and did not sit, the people stood up along with him. When he finished the prayer and the people expected him to give the salutation, he said “God is most great" while sitting and made two prostrations before giving the salutation. Then he gave it. (Bukhari and Muslim.)
Source
Mishkat al-Masabih(مشكاة المصابيح)
Prayer
Hadith Number
958