Clarifying that faith decreases with shortcoming in obedience, and the word Kufr may be used with regard to matters other than dsbelief in Allah, such as ingratitude for blessings and not fulfilling one's duties Sahih Muslim 80 b
Arabic hadith text
وَحَدَّثَنَا يَحْيَى بْنُ أَيُّوبَ، وَقُتَيْبَةُ، وَابْنُ، حُجْرٍ قَالُوا حَدَّثَنَا إِسْمَاعِيلُ، - وَهُوَ ابْنُ جَعْفَرٍ - عَنْ عَمْرِو بْنِ أَبِي عَمْرٍو، عَنِ الْمَقْبُرِيِّ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم بِمِثْلِ مَعْنَى حَدِيثِ ابْنِ عُمَرَ عَنِ النَّبِيِّ صلى الله عليه وسلم
Translation
A hadith like this as narrated by Ibn 'Umar has also been transmitted by Abu Huraira.