TABARANI 14137:
from Kathīr b. ʿAbdullāh b. ʿAmr b. ʿAwf from his father from his grandfather —
[Machine] That the Messenger of Allah ﷺ used to say Takbir (Allahu Akbar) seven times in the first rak'ah and five times in the second rak'ah before recitation on the two Eids.
الطبراني ١٤١٣٧:
عن كثير بن عبد الله بن عمرو بن عوف عن أبيه عن جده —
أَنَّ رَسُولَ اللهِ ﷺ كَانَ يُكَبِّرُ فِي الْعِيدَيْنِ فِي الرَّكْعَةِ الْأُولَى سَبْعَ تَكْبِيرَاتٍ وَفِي الرَّكْعَةِ الثَّانِيَةِ خَمْسَ تَكْبِيرَاتٍ قَبْلَ الْقِرَاءَةِ
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