promise (n.) Look up promise at Dictionary.com
c.1400, "a pledge, vow," from Old French promesse "promise, guarantee, assurance" (13c.) and directly from Latin promissum "a promise," noun use of neuter past participle of promittere "send forth; let go; foretell; assure beforehand, promise," from pro- "before" (see pro-) + mittere "to put, send" (see mission). The ground sense is "declaration made about the future, about some act to be done or not done."
promise (v.) Look up promise at Dictionary.com
c.1400, from promise (n.). Related: Promised; promising. Promised land (1530s) is a reference to the land of Canaan promised to Abraham and his progeny (Hebrew xi:9, etc.; Greek ten ges tes epangelias).