Jabatan Keselamatan Dalaman bertanggungjawab ke atas segala perkara yang berkaitan dengan keselamatan di dalam Negara Islam, dengan menggunakan pasukan tentera bagi tujuan tersebut.

The department of Internal Security oversees everything connected with security inside the Islamic State, utilising the military forces for this purpose.

Keselamatan dalaman, serta keselamatan luaran, dipelihara oleh tentera. Fungsi (polis) berada di bawah kawalan tentera. Nabi ﷺ melantik Qays ibn Sa‘ad sebagai ketua keselamatan. Beliau bertugas melindungi Nabi ﷺ ketika baginda berada di dalam majlis. Adalah wajar bagi pasukan keselamatan dalaman mengekalkan prosedur tentera biasa, supaya ia kekal teratur, cekap dan diselaraskan sebagaimana tentera biasa. Pasukan keselamatan dalaman mempunyai fungsi pengawasan, memelihara undang-undang dan ketertiban, serta melaksanakan undang-undang yang diterima pakai oleh Negara. Nabi ﷺ melantik ‘Abdullah ibn Mas‘ud sebagai ketua assas (pengawasan). Pengawasan oleh bahagian tentera ini tidak bermakna mencerobohi privasi orang lain. Sebaliknya, ia digunakan untuk pengawasan umum. Oleh kerana memelihara keselamatan dalaman ialah tindakan yang menjadi tanggungjawab Negara, Negara tidak berhak mengenakan bayaran ke atas rakyat Negara bagi melaksanakan fungsi ini.

The internal security, as well as the external security, is preserved by the army. The functions of the (police) are under the control of the army. The Prophet (saw) appointed Qays ibn Sa‘ad as the head of security. He was there to protect the Prophet (saw) when he was in Majlis. It is preferable for the internal security force to maintain the procedures of the regular army, so that it will remain organised, efficient, and co-ordinated as in a regular army. The internal security force has the function of surveillance, preserving law and order, and to execute the laws adopted by the State. The Prophet (saw) appointed ‘Abdullah ibn Mas‘ud as the leader of assas (surveillance). Surveillance, by this part of the army, does not mean to invade the privacy of others. Rather, its usage is for general surveillance. Since maintaining the internal security is an action the State is responsible for, it has no right to levy payments on the citizens of the State for executing this function.