Sunan Abi Dawud 4666
سنن أبي داود#4666SahihQais b. ‘Abbad said :I said to ‘All (Allah be pleased with him) : Tell me about this march of yours. Is this an order that the Messenger of Allah (May peace be upon him) had given you, or is this your opinion that you have? He said: The Messenger of Allah (May peace be upon him) did not give me any order; but this is an opinion that I have
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih Isnaad
Muhammad Muhyi Al-Din Abdul HamidSahih Isnaad
Zubair Ali ZaiSahih
In-book reference: 42:71