Hadith
وَحَدَّثَنَاهُ مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا ابْنُ أَبِي عَدِيٍّ، عَنْ سَعِيدٍ، عَنْ قَتَادَةَ، بِهَذَا الإِسْنَادِ أَنَّهُ رَأَى نَبِيَّ اللَّهِ صلى الله عليه وسلم وَقَالَ حَتَّى يُحَاذِيَ بِهِمَا فُرُوعَ أُذُنَيْهِ .
This hadith has been transmitted by Qatada with the same chain of transmitters that he saw the Messenger of Allah (ﷺ) doing this (i.e. raising his hands) till they were opposite the lobes of ears
Sahih
Sahih Muslim 866 ·Book 4, Hadith 29·Also available on sunnah.com·