prophecy / prophesy are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
prophecy: (noun) knowledge of the future (usually said to be obtained from a divine source). (noun) a prediction uttered under divine inspiration.
prophesy: (verb) predict or reveal through, or as if through, divine inspiration.
prophecy: p·r·AA·f·ah·s·iy
prophesy: NA
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)