Sahih al-Bukhari 26
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 ‏"‏‏.‏