صحيح البخاري

Narrated Ibn `Abbas:

When (the dead body of) `Umar was put on his deathbed, the people gathered around him and invoked (Allah) and prayed for him before the body was taken away, and I was amongst them. Suddenly I felt somebody taking hold of my shoulder and found out that he was `Ali bin Abi Talib. `Ali invoked Allah's Mercy for `Umar and said, "O `Umar! You have not left behind you a person whose deeds I like to imitate and meet Allah with more than I like your deeds. By Allah! I always thought that Allah would keep you with your two companions, for very often I used to hear the Prophet (ﷺ) saying, 'I, Abu Bakr and `Umar went (somewhere); I, Abu Bakr and `Umar entered (somewhere); and I, Abu Bakr and `Umar went out."'