Sahih Bukhari

Narrated Ibn `Umar:Allah's Messenger (ﷺ) said, ""Amongst the trees, there is a tree, the leaves of which do not fall and is like a Muslim. Tell me the name of that tree."" Everybody started thinking about the trees of the desert areas. And I thought of the date-palm tree but felt shy to answer the others then asked, ""What is that tree, O Allah's Messenger (ﷺ) ?"" He replied, ""It is the date-palm tree