The following quotation comes from Ibn Khaldun's Muqaddimah, Chapter 3.31.
In the Muslim community, the holy war1 is a religious duty2, because of the universalism of the (Muslim) mission3 and (the obligation to) convert everybody4 to Islam either by persuasion or by force5.
- What makes a war holy? The mission: to establish Islam6 and make Allah's word superior7. What would profane a holy war? Embezzling the spoils8, which includes killing enemy women and children because "they are property for Muslims"9.
- What makes holy war a religious duty? Surah al-Baqarah 2:216 "Jihad is ordained for you"... and the commands to fight found in Surah al-Anfal 8:39 and Surah at-Taubah 9:29. They are confirmed by Sahih Bukhari 1.8.387.
- What makes the Muslim mission universal? This saying of Moe found in Sahih Bukhari 1.7.331: "Every Prophet used to be sent to his nation only but I have been sent to all mankind."
- What is the basis of the obligation to convert everybody? In Surah al-Anfal 39, one of the compound terminal conditions is that only Allah be worshiped ["and the religion (worship) will all be for Allâh Alone"].
- What is the basis of conversion by force? In Sahih Muslim 19.4294, Moe's order to his commanders in the field is quoted. He told them, when they meet the enemy, to offer three choices, to submit, submit and join Jihad or to pay jizya and live as second class citizens. If the demand for Jizya was refused, he ordered his commanders to fight the disbelievers. In Surah al-Imran 3:110, Allah refers to believing Muslims as "the best of peoples ever raised up for mankind". That ayeh is explained in Sahih Bukhari 6.60.80 "...means, the best of peoples for the people, as you bring them with chains on their necks till they embrace Islam."
- The translators of the Noble Qur'an define Jihad in a footnote to Surah al-Baqarah 2:190. Establishment of Islam is one of the elements of that definition: "...By Jihâd Islâm is established..."
- In the footnote cited above, the quote continues with: "Allâh’s Word is made superior...". That objective is clearly stated in Surah at-taubah 9:33 "...to make it superior over all religions...". This is confirmed in Sahih Bukhari 9.93.550 "..."The one who fights that Allah's Word (Islam) should be superior, fights in Allah's Cause."...
- The orders in Sahih Muslim 19.4294 include " ... Make a holy war, do not embezzle the spoils...".
- The quote comes from The Religious and Moral Doctrine On Jihad by Ibn Taimiyyah .