Al-Adab Al-Mufrad, Book 30, Hadith 546 (English) ⓘ

'Abdullah ibn 'Amr reported that the Prophet, may Allah bless him and grant him peace, said, "Anyone who has love for his brother in Allah and for Allah should say, 'I love you for Allah,' and they will both enter the Garden. The one who has love for someone in Allah has a degree over the one he loves because of his love."

حَدَّثَنَا الْمُقْرِئُ، قَالَ‏:‏ حَدَّثَنَا عَبْدُ الرَّحْمَنِ، عَنْ عَبْدِ اللهِ بْنِ يَزِيدَ، عَنْ عَبْدِ اللهِ بْنِ عَمْرٍو، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ‏:‏ مَنْ أَحَبَّ أَخًا لِلَّهِ، فِي اللهِ، قَالَ‏:‏ إِنِّي أُحِبُّكَ لِلَّهِ، فَدَخَلاَ جَمِيعًا الْجَنَّةَ، كَانَ الَّذِي أَحَبَّ فِي اللهِ أَرْفَعَ دَرَجَةً لِحُبِّهِ، عَلَى الَّذِي أَحَبَّهُ لَهُ‏.‏