It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: In Paradise, there is a tree such that if a rider were to travel in its shade for a hundred years, he would still not be able to cross it; that is the Tree of Eternity.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 9950
Hadith Gradingحکم دارالسلام:حديث صحيح دون قوله: « شجرة الخلد » خ: 4881، م: 2826، وهذا إسناد ضعيف، أبو الضحااك ، مجهول