Present participle of apostatize: the ongoing action of abandoning one's religious faith or previously held principles.
From apostatize with the gerund/present participle suffix -ing. Maintains the sense of 'standing away' (Greek apo- + stasis) in a continuous or progressive form.
The word became especially loaded during the Protestant Reformation when both Catholics and Protestants accused each other of 'apostatizing'—meaning the same exact person could be a loyal believer to their own side and an apostatizer to their opponents, making it one of history's most perspective-dependent words.
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