Message
Middle English: from Old French, based on Latin missus, past participle of mittere ‘send’.
wiktionary
From Middle English message, from Old French message, from Late Latin missaticum, from Latin mittere, missum(“to send”), ultimately from Proto-Indo-European *meyth₂-(“to exchange”). Displaced native Old English ærende which is survived in English errand.
etymonline
message (n.)
c. 1300, "a communication transmitted via a messenger, a notice sent through some agency," from Old French message "message, news, tidings, embassy" (11c.), from Medieval Latin missaticum, from Latin missus "a sending away, sending, dispatching; a throwing, hurling," noun use of past participle of mittere "to release, let go; send, throw" (see mission).
The Latin word is glossed in Old English by ærende. Specific religious sense of "divinely inspired communication via a prophet" (1540s) led to transferred sense of "the broad meaning (of something)," which is attested by 1828. To get the message "understand" is by 1960.
message (v.)
"to send messages," 1580s, from message (n.). Marked as "obsolete" in Century Dictionary (1895). Meaning "to send an electronic message" is by 1992. Related: Messaged; messaging.