There are three qualities for which anyone who is characterised by them will relish the sweetness of faith: he to whom Allah and His Messenger are dearer than all else; he who loves a man for Allah's sake alone; and he who has as great an abhorrence of returning to unbelief after Allah has rescued him from it as he has of being cast into Hell.
عَنِ النَّبِيِّ ﷺ قَالَ ثَلاَثٌ مَنْ كُنَّ فِيهِ وَجَدَ بِهِنَّ حَلاَوَةَ الإِيمَانِ مَنْ كَانَ اللَّهُ وَرَسُولُهُ أَحَبَّ إِلَيْهِ مِمَّا سِوَاهُمَا وَأَنْ يُحِبَّ الْمَرْءَ لاَ يُحِبُّهُ إِلاَّ لِلَّهِ وَأَنْ يَكْرَهَ أَنْ يَعُودَ فِي الْكُفْرِ بَعْدَ أَنْ أَنْقَذَهُ اللَّهُ مِنْهُ كَمَا يَكْرَهُ أَنْ يُقْذَفَ فِي النَّارِ