حَدَّثَنَا يَحْيَى عَنْ زُهَيْرٍ قَالَ حَدَّثَنِي أَبُو إِسْحَاقَ عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْأَسْوَدِ عَنِ الْأَسْوَدِ وَعَلْقَمَةَ عَنْ عَبْدِ اللَّهِ قَالَ أَنَا رَأَيْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يُكَبِّرُ فِي كُلِّ خَفْضٍ وَرَفْعٍ وَقِيَامٍ وَقُعُودٍ وَيُسَلِّمُ عَنْ يَمِينِهِ وَعَنْ يَسَارِهِ حَتَّى يُرَى بَيَاضُ خَدَّيْهِ أَوْ خَدِّهِ وَرَأَيْتُ أَبَا بَكْرٍ وَعُمَرَ يَفْعَلَانِ ذَلِكَ
مسند امام احمد بن حنبل · Hadith 3660
It was narrated that 'Abdullah (RA) said: i saw the Messenger of Allah (PBUH) saying takbecr every time he lowered or raised his head (in prayer), and every time he moved to stand or sit, and he said the salam to his right and to his left, until the whiteness of his cheeks - or cheek - became visible, and I saw Abu Bakr and 'Umar doing likewise.
Sanad
حَدَّثَنَا يَحْيَى عَنْ زُهَيْرٍ قَالَ حَدَّثَنِي أَبُو إِسْحَاقَ عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْأَسْوَدِ عَنِ الْأَسْوَدِ وَعَلْقَمَةَ عَنْ عَبْدِ اللَّهِ