مِشْكَاةُ الْمَصَابِيحِ
Mishkat al-Masabih 943
Prayer
The Supplication of the Tashahhud - Section 1
وَعَنْ عَامِرِ بْنِ سَعْدٍ عَنْ أَبِيهِ قَالَ: كُنْتُ أَرَى رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يُسَلِّمُ عَنْ يَمِينِهِ وَعَنْ يَسَارِهِ حَتَّى أرى بَيَاض خَدّه. رَوَاهُ مُسلم
‘Amir b. Sa'd quoted his father as saying that he used to see God’s Messenger giving the salutation* to his right and his left, so that he could see the whiteness of his cheek. *1. I.e. pronouncing the taslim. Muslim transmitted it.
Mishkat al-Masabih, 943صَحِيح (الألباني)