Sahih Bukhari Volume 6, Book 65, Hadith 4516

وَزَادَ عُثْمَانُ بْنُ صَالِحٍ عَنِ ابْنِ وَهْبٍ، قَالَ أَخْبَرَنِي فُلاَنٌ، وَحَيْوَةُ بْنُ شُرَيْحٍ، عَنْ بَكْرِ بْنِ عَمْرٍو الْمَعَافِرِيِّ، أَنَّ بُكَيْرَ بْنَ عَبْدِ اللَّهِ، حَدَّثَهُ عَنْ نَافِعٍ، أَنَّ رَجُلاً، أَتَى ابْنَ عُمَرَ فَقَالَ يَا أَبَا عَبْدِ الرَّحْمَنِ مَا حَمَلَكَ عَلَى أَنْ تَحُجَّ عَامًا وَتَعْتَمِرَ عَامًا، وَتَتْرُكَ الْجِهَادَ فِي سَبِيلِ اللَّهِ عَزَّ وَجَلَّ، وَقَدْ عَلِمْتَ مَا رَغَّبَ اللَّهُ فِيهِ قَالَ يَا ابْنَ أَخِي بُنِيَ الإِسْلاَمُ عَلَى خَمْسٍ إِيمَانٍ بِاللَّهِ وَرَسُولِهِ، وَالصَّلاَةِ الْخَمْسِ، وَصِيَامِ رَمَضَانَ، وَأَدَاءِ الزَّكَاةِ، وَحَجِّ الْبَيْتِ‏.‏ قَالَ يَا أَبَا عَبْدِ الرَّحْمَنِ، أَلاَ تَسْمَعُ مَا ذَكَرَ اللَّهُ فِي كِتَابِهِ ‏{‏وَإِنْ طَائِفَتَانِ مِنَ الْمُؤْمِنِينَ اقْتَتَلُوا فَأَصْلِحُوا بَيْنَهُمَا‏}‏ ‏{‏إِلَى أَمْرِ اللَّهِ‏}‏ ‏{‏قَاتِلُوهُمْ حَتَّى لاَ تَكُونَ فِتْنَةٌ‏}‏ قَالَ فَعَلْنَا عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم وَكَانَ الإِسْلاَمُ قَلِيلاً، فَكَانَ الرَّجُلُ يُفْتَنُ فِي دِينِهِ إِمَّا قَتَلُوهُ، وَإِمَّا يُعَذِّبُوهُ، حَتَّى كَثُرَ الإِسْلاَمُ فَلَمْ تَكُنْ فِتْنَةٌ

Narrated Nafi (through another group of sub-narrators): A man came to Ibn 'Umar and said, "O Abu Abdur Rahman! What made you perform Hajj in one year and Umra in another year and leave the Jihad for Allah' Cause though you know how much Allah recommends it?" Ibn 'Umar replied, "O son of my brother! Islam is founded on five principles, i.e. believe in Allah and His Apostle, the five compulsory prayers, the fasting of the month of Ramadan, the payment of Zakat, and the Hajj to the House (of Allah)." The man said, "O Abu Abdur Rahman! Won't you listen to why Allah has mentioned in His Book: 'If two groups of believers fight each other, then make peace between them, but if one of then transgresses beyond bounds against the other, then you all fight against the one that transgresses. (49.9) and: "And fight them till there is no more affliction (i.e. no more worshiping of others along with Allah)." Ibn 'Umar said, "We did it, during the lifetime of Allah's Apostle when Islam had only a few followers. A man would be put to trial because of his religion; he would either be killed or tortured. But when the Muslims increased, there was no more afflictions or oppressions."