That is so, so I said to Wuhaib ibn Khalid, and Wuhaib ibn Khalid said to him: "Do you do something that I have not seen anyone do?" Ibn Tawus said: "I saw my father do it," and my father said: "I saw Ibn 'Abbas do it," and I do not know except that he said: "The Prophet, peace be upon him, used to do it."(1)

741 - Nasr ibn 'Ali narrated to us, 'Abd al-A'la informed us, 'Ubaidullah narrated to us, from Nafi', from Ibn 'Umar, that when he entered into prayer he would say the takbir and raise his hands, and when he bowed, and when he said: "Allah hears the one who praises Him," and when he stood up from the two rak'ahs he raised his hands, and he attributed that to the Messenger of Allah, peace be upon him.(2)

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(1) Its chain is weak due to the weakness of al-Nadr ibn Kathir al-Sa'di. Al-Nasa'i also narrated it in "Al-Kubra" (736) via the chain of al-Nadr ibn Kathir, with this chain.
(2) Its chain is authentic. The author's statement: "The correct view is that the saying of Ibn 'Umar is not marfu' (attributed to the Prophet)," is refuted, for more than one narrator has narrated it from Nafi', from Ibn 'Umar, as marfu'. Al-Bukhari declared its marfu' status authentic, and al-Daraqutni said in "Al-'Ilal" as quoted in "Fath al-Bari" 2/222: "The closest to what is correct is the saying of 'Abd al-A'la," meaning marfu'. We say: It has already preceded as marfu' via the chain of Salim from Ibn 'Umar under number (721).
Al-Bukhari also narrated it in "Al-Sahih" (739), and al-Bayhaqi 2/70 and 136 via the chain of 'Abd al-A'la ibn 'Abd al-A'la, with this chain.
'Abd al-Wahhab al-Thaqafi differed with 'Abd al-A'la regarding 'Ubaidullah, narrating it as mauquf (stopped at the Companion), as found in al-Bukhari's "Raf' al-Yadain" (80).
Ahmad also narrated it (5762), and al-Bukhari in "Raf' al-Yadain" (52) and (53), and al-Tahawi in "Sharh Mushkil al-Athar" (5832), and al-Bayhaqi 2/70 via the chain of Hammad ibn Salama, and al-Bayhaqi 2/70-71 via the chain of Ibrahim ibn Tahman, both from Ayyub ibn Abi Tamima, and Ahmad (6164), and al-Daraqutni (1136/2) via the chain of Salih ibn Kaisan, and al-Bayhaqi 2/70-71 via the chain of Musa ibn 'Uqba — all three of them (Ayyub, Salih, and Musa) from Nafi', from Ibn 'Umar, as marfu'.