The Messenger of Allah ﷺ most frequently made this supplication on the day of Arafah, "There is no god but Allah alone, with no partner. To Him belongs the dominion and to Him belongs all praise. In His hand is all good, and He has power over everything."
حدثنا روح حدثنا محمد بن أبي حميد أخبرني
كان أكثر دعاء رسول الله ﷺ يوم عرفة لا إله إلا الله وحده لا شريك له له الملك وله الحمد بيده الخير وهو على كل شيء قدير
Its chain of transmission is daif. Muhammad bin Abu Humayd Ansari Zarqi, whose nickname was Hammad, and his weakness has already been explained at 1444.Haythami mentioned the hadith in Majma al-Zawaid 3:252, and said, "Ahmad related it, and its narrators are trustworthy." But in reality it should not be counted among the additional narrations, for Tirmidhi related it in 4:285, with a similar meaning, through the route of Abdullah bin Nafi, who is Saigh, from Hammad bin Abu Humayd, from Amr bin Shuayb, with this chain of transmission.Its wording is, "The best supplication is the supplication of the day of Arafah, and the best thing that I and the prophets before me have said is, there is no god but Allah alone, with no partner, His is the dominion and His is the praise, and He has power over all things."Tirmidhi said, "This is a hasan gharib hadith from this route." Hammad bin Abu Humayd is Muhammad bin Abu Humayd, who is Abu Ibrahim Ansari Madini, and he is not considered strong by the people of hadith.Munziri mentioned it in Targheeb 2:242, from the narration of Tirmidhi, and quoted from him his grading of it as hasan. Majd bin Taymiyyah mentioned the two narrations in Muntaqa at 2591 and 2592, and treated them as two narrations of a single hadith, and he was correct.See also 6740.