Here is the law of Jihad…
(O: Jihad means to war against non-Muslims and is etymologically derived from the word mujahada, signifying warfare to establish the religion. And it is the lesser jihad. As for the greater jihad, it is spiritual warfare against the lower self (nafs), which is why the Prophet (Allah bless him and give him peace) said as he was returning from jihad.
The scriptural basis for jihad, prior to scholarly consensus is such Koranic verses as:
(1) “Fighting is prescribed for you” (Koran 2:216)
(2) “Slay them wherever you find them” (Koran 4:89)
(3) “Fight the idolaters utterly” (Koran 9:36);
and such Hadiths as the one related by Bukhari and Muslim that the Prophet (Allah bless him and give him peace) said:
“I have been commanded to fight people until they testify that there is no god but Allah and Muhammad is the Messenger of Allah, and perform the prayer, and pay zakat . If they say it, they have saved their blood and possessions from me, except from the rights of Islam over them. And their final reckoning is with Allah”;
and the hadith reported by Muslim,
“To go forth in the morning or evening to fight in the path of Allah is better than the whole world and everything in it.”
09.1 Jihad is a communal obligation.
O9.6 It is offensive to conduct a military expedition against hostile non-Mulims without the caliph’s permission. (A: Though if there I s no caliph, no permission is required).
WHO IS OBLIGATED TO FIGHT IN JIHAD
O9.4 Those called upon (o: to perform jihad when it is a communical obligation) are every able-bodied man who has reached puberty and is sane.