Narrated An-Nu'man ibn Bashir:
I am the one who is best informed of the time of this prayer, i.e. the night prayer. The Messenger of Allah (ﷺ) used to offer it at the hour when the moon went down on its third night.
It was narrated that An-Nu'man bin Bashir said: "By Allah, I am the most knowledgeable of people about the time of the 'Isha' prayers. The Prophet (ﷺ) used to pray it when the moon set on the third night of the month."
An-Nu'man bin Bashir said:
"I am the most knowledgeable among the people about the prescribed time of this prayer: Allah's Messenger (ﷺ) would pray it when the moon set on the third (of the month)."