Sunan An Nasai
5432
It was narrated that 'Uqbah bin 'Amir Al-Juhani said:
While I was leading the Messenger of Allah [SAW] on his mount on a military campaign, he said: 'O 'Uqbah, say!' I listened, then he said: 'O 'Uqbah, say!' I listened, then he said it a third..
READ COMPLETE