I never heard the Messenger of Allah ﷺ begin a supplication except that he opened it with, "Glory be to my Lord the Most High, the Exalted, the Bestower."Salama said, "I pledged allegiance to the Messenger of Allah ﷺ among those who pledged to him beneath the tree. Later I passed by him while he was with a group of people, and he said, 'Pledge allegiance, Salama.'I replied, 'I have already done so.'He said, 'Do it again.' So I pledged allegiance to him a second time."
قال حدثنا عبد الصمد قال حدثنا عمر بن راشد اليمامي قال حدثنا
ما سمعت رسول الله ﷺ يستفتح دعاء إلا استفتحه بسبحان ربي الأعلى العلي الوهاب وقال سلمة بايعت رسول الله ﷺ فيمن بايعه تحت الشجرة ثم مررت به بعد ذلك ومعه قوم فقال بايع يا سلمة فقلت قد فعلت قال وأيضا فبايعته الثانية
No references are available.
Its isnad is daif, because of Umar bin Rashid, but the hadith is sahih and has already appeared at 16470, and it is found in Muslim 3/1433, number 1807.