The war department is one of the State’s organisations, and its head is called the amir of jihad, rather than the manager of jihad. This is because the Messenger (PBUH) used to give to the leaders of the army the names of amirs.. Ibn Sa’d narrated that the Messenger of Allah (PBUH) said: .

The amir of the people is Zayd ibn Haritha; if he was killed then the amir is Ja’far ibn Abi Talib; and if was killed the amir is Abdullah ibn Ruwahah; and if was killed let the Muslims choose one man from among them and make him their amir.” .

Al-Bukhari narrated that Abdullah ibn ‘Umar (ra) said: .

“The Messenger of Allah (PBUH) appointed Zayd ibn Haritha as amir in the expedition of Mu’tah…” Al-Bukhari narrated has from the hadith of Salamah ibn Al-Akwa’: “I went on an expedition with Zayd; he was appointed amir over us”. .

Al-Bukhari and Muslim narrated that Abdullah ibn ‘Umar (ra) said: .

The Prophet (PBUH) sent an army and appointed Usama ibn Zayd as an amir over them. So some people defamed his leadership, so the Prophet (PBUH) said: .

‘If you defame his leadership you defamed the leadership of his father before. By Allah! He is worthy of leadership…’” [Bukhari, Sahih, #4250 and Muslim, Sahih, #2436]. The Sahabah used to call the army of Mu’tah the army of amirs. Muslim narrated from Ibn Buraydah, he said: “The Messenger of Allah ( PBUH) used to advise the person whom he appointed as amir over an army or an expedition …” ..

The war department takes charge of all the issues connected to the armed forces, in terms of the army, equipment, weapons, facilities, ammunition and the like. This is in addition to military academies, military missions and whatever is necessary of Islamic and general culture for the army and everything related to war and planning of it. The task of sending spies against the belligerent disbelievers is also the role of the war department and there should be a special section for this purpose. The evidences for this are well known in the seerah of the Messenger (PBUH). .