“Zaid bin Arqan used to say the Takbir four times in the funeral prayer, and he said the Takbir five times for one funeral. I asked him (about that) and he said: ‘The Messenger of Allah ﷺ used to do that.’”  

كَانَ رَسُولُ اللَّهِ ﷺ يُكَبِّرُهَا  

It was narrated from Kathir bin ‘Abdullah, from his father, from his grandfather, that the Messenger of Allah ﷺ said the Takbir five times.  

أَنَّ رَسُولَ اللَّهِ ﷺ كَبَّرَ خَمْسًا