To stand Straight with calmness on raising the head from bowing

Sahih al-Bukhari · Book 10 · Hadith 800

حَدَّثَنَا أَبُو الْوَلِيدِ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ ثَابِتٍ، قَالَ كَانَ أَنَسٌ يَنْعَتُ لَنَا صَلاَةَ النَّبِيِّ صلى الله عليه وسلم فَكَانَ يُصَلِّي وَإِذَا رَفَعَ رَأْسَهُ مِنَ الرُّكُوعِ قَامَ حَتَّى نَقُولَ قَدْ نَسِيَ‏.‏

Narrated Thabit: Anas used to demonstrate to us the prayer of the Prophet (ﷺ) and while demonstrating, he used to raise his head from bowing and stand so long that we would say that he had forgotten (the prostration).

Sahih al-Bukhari · Book 10 · Hadith 801

حَدَّثَنَا أَبُو الْوَلِيدِ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنِ الْحَكَمِ، عَنِ ابْنِ أَبِي لَيْلَى، عَنِ الْبَرَاءِ ـ رضى الله عنه ـ قَالَ كَانَ رُكُوعُ النَّبِيِّ صلى الله عليه وسلم وَسُجُودُهُ وَإِذَا رَفَعَ رَأْسَهُ مِنَ الرُّكُوعِ وَبَيْنَ السَّجْدَتَيْنِ قَرِيبًا مِنَ السَّوَاءِ‏.‏

Narrated Al-Bara': The bowing, the prostrations, the period of standing after bowing and the interval between the two prostrations of the Prophet (ﷺ) used to be equal in duration .