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كتاب الإيمان
2
Belief
(18)
Chapter: Whoever says that faith is action (good deeds)
(18)
باب مَنْ قَالَ إِنَّ الإِيمَانَ هُوَ الْعَمَلُ
لِقَوْلِ اللَّهِ تَعَالَى: {وَتِلْكَ الْجَنَّةُ الَّتِي أُورِثْتُمُوهَا بِمَا كُنْتُمْ تَعْمَلُونَ}.
وَقَالَ عِدَّةٌ مِنْ أَهْلِ الْعِلْمِ فِي قَوْلِهِ تَعَالَى: {فَوَرَبِّكَ لَنَسْأَلَنَّهُمْ أَجْمَعِينَ عَمَّا كَانُوا يَعْمَلُونَ} عَنْ قَوْلِ لاَ إِلَهَ إِلاَّ اللَّهُ.
وَقَالَ: {لِمِثْلِ هَذَا فَلْيَعْمَلِ الْعَامِلُونَ}.

Narrated Abu Huraira:

Allah's Messenger (ﷺ) was asked, "What is the best deed?" He replied, "To believe in Allah and His Apostle (Muhammad). The questioner then asked, "What is the next (in goodness)? He replied, "To participate in Jihad (religious fighting) in Allah's Cause." The questioner again asked, "What is the next (in goodness)?" He replied, "To perform Hajj (Pilgrim age to Mecca) 'Mubrur, (which is accepted by Allah and is performed with the intention of seeking Allah's pleasure only and not to show off and without committing a sin and in accordance with the traditions of the Prophet)."

حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، وَمُوسَى بْنُ إِسْمَاعِيلَ، قَالاَ حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، قَالَ حَدَّثَنَا ابْنُ شِهَابٍ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم سُئِلَ أَىُّ الْعَمَلِ أَفْضَلُ فَقَالَ ‏"‏ إِيمَانٌ بِاللَّهِ وَرَسُولِهِ ‏"‏‏.‏ قِيلَ ثُمَّ مَاذَا قَالَ ‏"‏ الْجِهَادُ فِي سَبِيلِ اللَّهِ ‏"‏‏.‏ قِيلَ ثُمَّ مَاذَا قَالَ ‏"‏ حَجٌّ مَبْرُورٌ ‏"‏‏.‏
Reference : Sahih al-Bukhari 26
In-book reference : Book 2, Hadith 19
USC-MSA web (English) reference : Vol. 1, Book 2, Hadith 26
  (deprecated numbering scheme)