It is narrated from Hazrat Anas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: None of you can be a believer until he likes for his brother or neighbor what he likes for himself, and if he loves anyone, he should love him only for the sake of Allah's pleasure.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 13875
Hadith Gradingحکم دارالسلام:إسناده صحيح، خ: 21، م: 43، وهو قطعة من حديث سلف برقم: 12765