He heard the Messenger of Allah (ﷺ) say: "When a person prostrates, seven parts of his body prostrate with him: his forehead, his two hands, his two knees and his two feet."
"I noticed the Messenger of Allah (ﷺ) was missing one night, and I found him when he was prostrating with his feet held upright, and he was saying: 'Allahumma, inni a'udhu biridaka min sakhatik, wa bimu'afatika min 'uqubatik, wa bika minka la uhsi thana'an 'alaika anta kama athnaita 'ala nafsik (O Allah, I seek refuge with Your pleasure from Your wrath, in Your forgiveness from Your punishment and in You from You. I cannot praise You enough, You are as You have praised Yourself.)"
"I came to Al-Madinah and said: 'I am going to watch the Messenger of Allah (ﷺ) pray. He said the takbir and raised his hands until I saw his thumbs near his ears. When he wanted to bow, he said the takbir and raised his hands. Then he raised his head and said: 'Sami Allahu liman hamidah (Allah hears the one who praises Him).' Then he said the takbir and prostrated, and his hands were in the same position in relation to his ears as when he started the prayer."
أَخْبَرَنَا عَلِيُّ بْنُ حُجْرٍ الْمَرْوَزِيُّ، قَالَ أَنْبَأَنَا شَرِيكٌ، عَنْ أَبِي إِسْحَاقَ، قَالَ وَصَفَ لَنَا الْبَرَاءُ السُّجُودَ فَوَضَعَ يَدَيْهِ بِالأَرْضِ وَرَفَعَ عَجِيزَتَهُ وَقَالَ هَكَذَا رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَفْعَلُ .
"Al-Bara' described the prostration to us. He places his hands on the ground and raised his posterior and said: 'This is what I saw the Messenger of Allah (ﷺ) doing."
"If I were in front of the Messenger of Allah (ﷺ) I would be able to see the whiteness of his armpits." (One of the narrators) Abu Mijlaz said: "It is as if he said that because he was praying."