كتاب الإيمان
Read the English translation first, with the original Arabic directly underneath.
Narrated Anas:
The Prophet (ﷺ) said, "Whoever possesses the following three qualities will taste the sweetness of faith: 1. The one to whom Allah and His Messenger become dearer than anything else. 2. Who loves a person and he loves him only for Allah's sake. 3. Who hates to revert to disbelief (Atheism) after Allah has brought (saved) him out from it, as he hates to be thrown in fire."
ثَلاَثٌ مَنْ كُنَّ فِيهِ وَجَدَ حَلاَوَةَ الإِيمَانِ مَنْ كَانَ اللَّهُ وَرَسُولُهُ أَحَبَّ إِلَيْهِ مِمَّا سِوَاهُمَا، وَمَنْ أَحَبَّ عَبْدًا لاَ يُحِبُّهُ إِلاَّ لِلَّهِ، وَمَنْ يَكْرَهُ أَنْ يَعُودَ فِي الْكُفْرِ بَعْدَ إِذْ أَنْقَذَهُ اللَّهُ، كَمَا يَكْرَهُ أَنْ يُلْقَى فِي النَّارِ