Narrated `Abdullah bin `Umar:
I saw Allah’s Messenger (ﷺ) opening the prayer with the Takbir and raising his hands to the level of his shoulders at the time of saying the Takbir, and on saying the Takbir for bowing he did the same; and when he said, “Sami`a l-lahu liman hamidah “, he did the same and then said, “Rabbana wa laka lhamd.” But he did not do the same on prostrating and on lifting the head from it.”
Narrated Salim bin `Abdullah:
My father said, “Allah’s Messenger (ﷺ) used to raise both his hands up to the level of his shoulders when opening the prayer; and on saying the Takbir for bowing. And on raising his head from bowing he used to do the same and then say “Sami`a l-lahu liman hamidah, Rabbana wa laka l-hamd.” And he did not do that (i.e. raising his hands) in prostrations.
Narrated by (Abdullah) Ibn Umar (RA):
The Prophet (ﷺ) used to raise his hands when he began to pray, when he wanted to bow, when he raised his head from bowing, and when he stood up after the first two rak’ahs, he would raise his hands likewise, level with his shoulders.
(An-Nasa’i 1182) [Sahih]
Salim narrated it on the authority of his father who reported:
I saw the Messenger of Allah (ﷺ) raising his hands apposite the shoulders at the time of beginning the prayer and before bowing down and after coming back to the position after bowing. but he did not raise them between two prostrations.
It was narrated that Ibn ‘Umar said:
“I saw the Messenger of Allah (ﷺ) raising his hands until they were parallel to his shoulders when he started the prayer, and when he bowed in Ruku’, and when he raised his head from Ruku’, but he did not raise them between the two prostrations.”
(Ibn Majah 858) [Sahih]
‘Abbas bin Sahl As-Sa’di said:
“Abu Humaid, Abu Usaid As-Sa’di, Sahl bin Sa’d, and Muhammad bin Maslamah came together and spoke about the prayer of the Messenger of Allah (ﷺ). Abu Humaid said: ‘I am the most knowledgeable of you about the prayer of the Messenger of Allah (ﷺ). The Messenger of Allah (ﷺ) stood up and said Allahu Akbar, and raised his hands, then he raised them when he said Allahu Akbar for Ruku’, then he stood up and raised his hands, and stood straight until every bone had returned to its place.’”
(Ibn Majah 863) [Sahih]
Narrated Nafi’:
Whenever Ibn `Umar started the prayer with Takbir, he used to raise his hands: whenever he bowed, he used to raise his hands (before bowing) and also used to raise his hands on saying, “Sami`a l-lahu liman hamidah”, and he used to do the same on rising from the second rak`a (for the 3rd rak`a). Ibn `Umar said: “The Prophet (ﷺ) used to do the same.”
Narrated from Nafi’:
When Ibn Umar (RA) did not see any (ignorant) person doing Ruku’ and after Ruku’, Rafa’ul Yadayan, he used to throw stones at him. The hadith is waived and it’s chain is authentic.
(Juj’ul Rafa’il Yadain, Hadith No. 13 Imam Bukhari)
Footnote: Imam Nawawi called this hadith Sahih in his book Al Majmu Sharhul Muhajab (3rd volume page 405). It is known from this hadith that it is permissible to stone someone who abandons the Sunnah. But it must be done by the ruler, like what Abdullah Ibn Umar did in this hadith, he was the Ameer al-Mu’minin at the time. And by the actions of the stranger who abandoned the Sunnah, it is evident that the stranger was not a companion.
There’s a hadith Nasa’i 1026 which says that the Prophet(ﷺ) stood and raised his hands the first time only, but this is a Daif hadith.
Thus, we know from the above Sahih Hadiths that Rafa’-Ul-Yadaain is a confirmed Sunnah of the Prophet (ﷺ). Almost all Hadiths attributed to Rafa’-Ul-Yadaain support this fact.
And our beloved Prophet(ﷺ) said:
“Pray as you have seen me praying”