The Messenger of Allah ﷺ said, "How can I be at ease when the bearer of the Horn has already placed it to his lips and bent his ear, awaiting the command to blow, ready to blow it the moment he is ordered."This seemed to weigh heavily upon the companions of the Prophet ﷺ, so he said to them, "Say, 'Allah is sufficient for us and the best disposer of affairs. Upon Allah we rely.'"
حدثنا سويد أخبرنا عبد الله أخبرنا أبو العلاء عن عطية
قال رسول الله ﷺ كيف أنعم وصاحب القرن قد التقم القرن واستمع الإذن متى يؤمر بالنفخ فينفخ فكأن ذلك ثقل على أصحاب النبي ﷺ فقال لهم قولوا حسبنا الله ونعم الوكيل على الله توكلنا
[Hasan] Coming: 3243. Ahmad also narrated it, 4/374, from the hadith of Khalid bin Tahman Abu Ala, with this wording, and it is found in Zuhd by Abdullah bin Mubarak, p. 557, no. 1597. Dhahabi said in Talkhis Mustadrak, 4/559, "Atiya is daif." The hadith has many corroborating narrations, some of which I mentioned in the takhrij of Nihayah fil-Fitan wal-Malahim, no. 489.