
credit to Bill Watterson

From Middle English doctor, doctour "an expert, authority on a subject" from Anglo-Norman doctour from Latin doctor (“teacher”) from doceō (“I teach”). Displaced native Middle English lerare "doctor, teacher" (from Middle English leren "to teach, instruct" from Old English lǣran, lēran "to teach, instruct, guide", compare Old English lārēow "teacher, master").

183 O ye who believe! Fasting is prescribed to you as it was prescribed to those before you, that ye may (learn) self-restraint,-
184 (Fasting) for a fixed number of days; but if any of you is ill, or on a journey, the prescribed number (should be made up) from days later. For those who can do it (with hardship), is a ransom, the feeding of one that is indigent. But he that will give more, of his own free will,- it is better for him. And it is better for you that ye fast, if ye only knew.
(AL-BAQARAH verses 183-184)