Sa‘d b. Abu Waqqas said

We went out with Allah's Messenger ﷺ from Mecca making for Medina, and when we were near ‘Azwaza’* he alighted, then raised his hands and made supplication to Allah for a time, after which he prostrated himself, remaining a long time in prostration. Then he stood up and raised his hands for a time, after which he prostrated himself, remaining a long time in prostration. Then he stood up and raised his hands for a time, after which he prostrated himself. He then said, “I begged my Lord and made intercession for my people, and He gave me a third of my people, so I prostrated myself in gratitude to my Lord. Then I raised my head and begged my Lord for my people and He gave me a third of my people, so I prostrated myself in gratitude to my Lord. Then I raised my head and begged my Lord for my people and He gave me the last third, so I prostrated myself in gratitude to my Lord.” *The name is spelt either as here with the alif mamduda, or with the alif maqsura (i.e. Azwaza). The reference is to a pass in the hills. Ahmad and Abu Dawud transmitted it.