عَنِ ابْنِ عَبَّاسٍ رَضِيَ اللَّهُ عَنْهُ قَالَ: تَدَبَّرْتُ صَلَاةَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فَرَأَيْتُهُ مُخَوِّيًا فَرَأَيْتُ بَيَاضَ إِبْطَيْهِ
Sayyiduna Abdullah bin Abbas (may Allah be pleased with him) says: I closely observed the prayer of the Messenger of Allah (peace and blessings be upon him), and I saw that he would lift his stomach away from the ground, and I also saw the whiteness of his armpits.