Ibn `Umar came to us and a man said (to him), "What do you think about 'Qit-alal-Fitnah' (fighting caused by afflictions)." Ibn `Umar said (to him), "And do you understand what an affliction is? Muhammad used to fight against the pagans, and his fighting with them was an affliction, (and his fighting was) not like your fighting which is carried on for the sake of ruling."
Sahih al-Bukhari Book 65, Hadith 173
← Previous Hadith That a man came to him (while two groups of Muslims were fighting) and said, "O Abu `Abdur Rahman! Don't you hear what Allah has mentioned in His Book: 'And if two groups of believers fight against each other...' (49.9) So what prevents you from fighting as Allah has mentioned in His Book?"' Ibn `Umar said, "O son of my brother! I would rather be blamed for not fighting because of this Verse than to be blamed because of another Verse where Allah says: 'And whoever kills a believer intentionally..." (4.93) Then that man said, "Allah says:-- 'And fight them until there is no more afflictions (worshipping other besides Allah) and the religion (i.e. worship) will be all for Allah (Alone)" (8.39) Ibn `Umar said, "We did this during the lifetime of Allah's Messenger (ﷺ) when the number of Muslims was small, and a man was put to trial because of his religion, the pagans would either kill or chain him; but when the Muslims increased (and Islam spread), there was no persecution." When that man saw that Ibn `Umar did not agree to his proposal, he said, "What is your opinion regarding `Ali and `Uthman?" Ibn `Umar said, "What is my opinion regarding `Ali and `Uthman? As for `Uthman, Allah forgave him and you disliked to forgive him, and `Ali is the cousin and son-in-law of Allah's Messenger (ﷺ) ." Then he pointed out with his hand and said, "And that is his daughter's (house) which you can see."

Sahih al-Bukhari Book 65, Hadith 172 Next Hadith → When the Verse:-- "If there are twenty steadfast amongst you, they will overcome two hundred." (8.65) was revealed, then it became obligatory for the Muslims that one (Muslim) should not flee from ten (non-Muslims). Sufyan (the sub-narrator) once said, "Twenty (Muslims) should not flee before two hundred (non Muslims)." Then there was revealed: 'But now Allah has lightened your (task)..' (8.66) So it became obligatory that one-hundred (Muslims) should not flee before two hundred (nonmuslims). (Once Sufyan said extra, "The Verse: 'Urge the believers to the fight. If there are twenty steadfast amongst you (Muslims) ..' was revealed.) Sufyan said, "Ibn Shabrama said, "I see that this order is applicable to the obligation of enjoining good and forbidding evil."

Sahih al-Bukhari Book 65, Hadith 174