—may Allah be pleased with him—, “Guard yourselves against people by suspecting the worst” (1). Yet it is not permissible to punish a Muslim merely because he is suspected (2).
For this reason, a ruler or scholar should be thoroughly acquainted with evil, its causes, and its signs. This includes knowledge of unbelief and wickedness, as well as the enemy’s circumstances in religious and worldly matters, so that he may guard against the harm arising from them (3).
Among the most beneficial measures was dispatching intelligence agents—that is, spies—into enemy territory and learning the path of unbelief. It has been related that one of the early Muslims said, “The bonds of Islam are undone one by one when someone grows up within Islam knowing nothing of the Jāhiliyya (the pre-Islamic state of ignorance)” (4). This is because someone who does not understand diseases and their causes may be lulled into complacency by good health and fail to guard against either the causes of disease or the disease itself; whereas [one who] knows its cause and sign is fit
(1) Al-Khattābī reported it in *al-ʿUzla* (p. 168). It has been transmitted with its chain stopping at Mutarrif ibn ʿAbd Allāh, and also as a *marfūʿ* hadith narrated from Anas. See *al-Maqāsid* (p. 23) and *al-Daʿīfa* (156).
(2) The wording in (ي، ز) reads: “This, then, is Umar’s instruction, although a ruler may not impose punishment merely because he suspects someone.” It is absent from (ب), while (ل) reads: “Nor is it permissible to punish a Muslim in an evil manner.”
(3) For further clarification of this issue, see Ibn al-Qayyim’s *al-Fawāʾid* (pp. 201–205).
(4) I could not locate it. The author cites it in several of his works and attributes it to Umar, as does his disciple Ibn al-Qayyim. However, a report conveying the same meaning was narrated by Ibn Abī Shayba (6:410), Ibn Saʿd (6:129), al-Hākim (4:475), and Abū Nuʿaym in *al-Hilya* (7:243), from Umar ibn al-Khattāb, who said: “By the Lord of the Kaaba, I know when the Arabs will perish.” A Muslim man stood and asked him, “When will they perish, O Commander of the Faithful?” He replied, “When their affairs are governed by someone with no firsthand experience of the Jāhiliyya and who did not accompany the Messenger, may Allah bless him and grant him peace.”