Sunan Abi Dawud Book 42, Hadith 57
The Prophet (ﷺ) said: Gabriel came and taking me by the hand showed the gate of Paradise by which my people will enter. AbuBakr then said: Messenger of Allah! I wish I had been with you so that I might have looked at it. The Messenger of Allah (ﷺ) then said: You, AbuBakr, will be the first of my people to enter Paradise.
The prophet of Allah (ﷺ) ascended Uhud, and Abu Bakr, ’Umar and 'Uthman followed him. It began to shake with them. The prophet of Allah (ﷺ) struck it with his foot and said: Be still, for only a prophet, an ever-truthful and two martyrs are on you.
No one of those who took the oath of allegiance under the tree will go to hell.