It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) entered the mosque, and then, in the complete hadith, he mentioned the story of the man who had entered the mosque. In it there is also that he (peace and blessings be upon him) said: "Then raise your head until you are standing perfectly straight."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2621
Abu Qilabah (may Allah have mercy on him) narrates from Malik bin al-Huwayrith (may Allah be pleased with him) that one day, at a time other than a prayer time, he said: Shall I not show you how the prayer of the Messenger of Allah (peace and blessings be upon him) was? Then he (may Allah be pleased with him) stood and stood at length, then he bowed and also remained long in bowing, then he raised his head from bowing and remained standing upright (for a while). Abu Qilabah (may Allah have mercy on him) said: Malik (may Allah be pleased with him) prayed like our shaykh Abu Burayd (may Allah have mercy on him). When Abu Burayd (may Allah have mercy on him) raised his head from the second prostration, he would (not stand up at once but would) sit, then stand up.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2622
(a) It is reported from Muhammad bin Amr bin Ata' that he was sitting with a group of the Companions of the Messenger of Allah (peace and blessings be upon him). Then he mentioned the complete hadith reported from Abu Humayd al-Sa'idi (may Allah be pleased with him), in which the method of the prayer of the Messenger of Allah (peace and blessings be upon him) is described. Abu Humayd (may Allah be pleased with him) said: When the Messenger of Allah (peace and blessings be upon him) raised his blessed head from bowing, he stood up straight until every vertebra of the back returned to its place.
(b) Abd al-Hamid bin Ja'far reported this from Muhammad bin Amr bin Ata'; he said: Every blessed bone of his (peace and blessings be upon him) would return to its place in balance.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2623
Thabit (may Allah have mercy on him) said: Sayyiduna Anas (may Allah be pleased with him) would describe to us the prayer of the Messenger of Allah (peace and blessings be upon him): when he (peace and blessings be upon him), while praying, raised his head from bowing, he would remain standing so long that we would think that perhaps he had forgotten.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2624
Thabit al-Bunani (may Allah have mercy on him) said: Sayyiduna Anas bin Malik (may Allah be pleased with him) said to us: I will lead you in prayer like the prayer of the Messenger of Allah (peace and blessings be upon him), just as he used to lead us. Hammad (may Allah have mercy on him) said: Thabit (may Allah have mercy on him) said: You do not pray the way Anas (may Allah be pleased with him) used to lead us in prayer. When he (may Allah be pleased with him) raised his head from bowing, he would remain standing upright until one would think that he had forgotten, and when he rose from prostration and sat, one would also think that perhaps he had forgotten.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2625
(a) Al-Hakam said: In the time of Ibn al-Ash'ath a man took control of Kufah (al-Hakam named him). He ordered Abu Ubaydah bin Abdullah bin Mas'ud (may Allah be pleased with him) to lead the people in prayer. While leading the prayer, when he raised his head from bowing, he would stand for as long as it took me to recite this supplication: 'Allahumma rabbana lakal-hamd mil'as-samawati wa mil'al-ardi wa mil'a ma shi'ta min shay'in ba'd, ahlath-thana'i wal-majd, la mani'a lima a'tayta wa la mu'tiya lima mana'ta wa la yanfa'u dhal-jaddi minkal-jadd' (O Allah, our Lord, to You belongs praise such as fills the heavens and the earth and fills whatever else You will thereafter. O You who are worthy of praise and glory, none can withhold what You give and none can give what You withhold, and the greatness of one possessed of greatness is of no benefit to him before You). Al-Hakam said: I mentioned this to Abd al-Rahman bin Abi Layla, and he said: I heard al-Bara' bin Azib (may Allah be pleased with him) say: "The standing of the Messenger of Allah (peace and blessings be upon him) in prayer, his bowing, (his standing) after rising from bowing, his prostration and his sitting between the two prostrations, the duration of all these positions was nearly equal."
(b) Shu'bah said: I mentioned this to Amr bin Murrah, and he said: I have seen Ibn Abi Layla, but his prayer was not like this.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2626