Sunan Abi Dawud 5189
سنن أبي داود#5189SahihNarrated AbuHurayrah: The Prophet (ﷺ) said: A man's messenger sent to another indicates his permission to enter
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih
In-book reference: 43:417