I saw ʿAbdullah bin ʿUmar crossing his legs while sitting in the prayer and I, a mere youngster in those days, did the same. Ibn ʿUmar forbade me to do so, and said, "The proper way is to keep the right foot propped up and bend the left in the prayer." I said questioningly, "But you are doing so (crossing the legs)." He said, "My feet cannot bear my weight."  

أَنْ تَنْصِبَ رِجْلَكَ الْيُمْنَى وَتَثْنِيَ الْيُسْرَى فَقُلْتُ إِنَّكَ تَفْعَلُ ذَلِكَ فَقَالَ إِنَّ رِجْلَىَّ لاَ تَحْمِلاَنِي  

I was sitting with some of the companions of Messenger of Allah ﷺ and we were discussing about the way of praying of the Prophet. Abu Humaid As-Saʿidi said, "I remember the prayer of Messenger of Allah ﷺ better than any one of you. I saw him raising both his hands up to the level of the shoulders on saying the Takbir; and on bowing he placed his hands on both knees and bent his back straight, then he stood up straight from bowing till all the vertebrate took their normal positions. In prostrations, he placed both his hands on the ground with the forearms away from the ground and away from his body, and his toes were facing the Qibla. On sitting In the second rakʿa he sat on his left foot and propped up the right one; and in the last rakʿa he pushed his left foot forward and kept the other foot propped up and sat over the buttocks."  

أَنَّهُ كَانَ جَالِسًا مَعَ نَفَرٍ مِنْ أَصْحَابِ النَّبِيِّ ﷺ فَذَكَرْنَا صَلاَةَ النَّبِيِّ ﷺ فَقَالَ أَبُو حُمَيْدٍ السَّاعِدِيُّ أَنَا كُنْتُ أَحْفَظَكُمْ لِصَلاَةِ رَسُولِ اللَّهِ ﷺ رَأَيْتُهُ إِذَا كَبَّرَ جَعَلَ يَدَيْهِ حِذَاءَ مَنْكِبَيْهِ وَإِذَا رَكَعَ أَمْكَنَ يَدَيْهِ مِنْ رُكْبَتَيْهِ ثُمَّ هَصَرَ ظَهْرَهُ فَإِذَا رَفَعَ رَأْسَهُ اسْتَوَى حَتَّى يَعُودَ كُلُّ فَقَارٍ مَكَانَهُ فَإِذَا سَجَدَ وَضَعَ يَدَيْهِ غَيْرَ مُفْتَرِشٍ وَلاَ قَابِضِهِمَا وَاسْتَقْبَلَ بِأَطْرَافِ أَصَابِعِ رِجْلَيْهِ الْقِبْلَةَ فَإِذَا جَلَسَ فِي الرَّكْعَتَيْنِ جَلَسَ عَلَى رِجْلِهِ الْيُسْرَى وَنَصَبَ الْيُمْنَى وَإِذَا جَلَسَ فِي الرَّكْعَةِ الآخِرَةِ قَدَّمَ رِجْلَهُ الْيُسْرَى وَنَصَبَ الأُخْرَى وَقَعَدَ عَلَى مَقْعَدَتِهِ وَسَمِعَ اللَّيْثُ يَزِيدَ بْنَ أَبِي حَبِيبٍ وَيَزِيدُ مِنْ مُحَمَّدِ بْنِ حَلْحَلَةَ وَابْنُ حَلْحَلَةَ مِنَ ابْنِ عَطَاءٍ قَالَ أَبُو صَالِحٍ عَنِ اللَّيْثِ كُلُّ فَقَارٍ وَقَالَ ابْنُ الْمُبَارَكِ عَنْ يَحْيَى بْنِ أَيُّوبَ قَالَ حَدَّثَنِي يَزِيدُ بْنُ أَبِي حَبِيبٍ أَنَّ مُحَمَّدَ بْنَ عَمْرٍو حَدَّثَهُ كُلُّ فَقَارٍ