ردة
Riddah
Leaving Islam. The Quran gives no worldly penalty for it; the classical law did, and Muslim scholars still differ.
What it means
The Quran says “there is no compulsion in religion” (2:256) and “whoever wishes, let him believe, and whoever wishes, let him disbelieve” (18:29). It speaks of those who believe and then disbelieve, believe again and disbelieve again (4:137), and of apostates whose deeds are void and who face the punishment of the Hereafter (2:217, 3:90), without mentioning any penalty in this world.
Often misunderstood as
That the Quran orders the killing of anyone who leaves Islam.
What the sources say
A hadith in Sahih al-Bukhari says “whoever changes his religion, kill him”. Most classical jurists applied it, usually after asking the person to repent. Others held that it applies to treason or rebellion, which is how the early wars with those who left Islam and fought the Muslims were remembered. Umar is reported to have asked, of a man who was killed, “why did you not imprison him for three days and give him bread each day, perhaps he would repent?” (al-Muwatta). Many contemporary scholars, citing 2:256, hold that belief cannot be compelled, and that only rebellion is punishable.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 33, listed as RIDDAH. The definition is restated here.