c. 1400, revelen, "disclose, divulge, make known (supernaturally or by divine agency, as religious truth)," from Old French reveler "reveal" (14c.), from Latin revelare "reveal, uncover, disclose," literally "unveil," from re- "back, again," here probably indicating "opposite of" or transition to an opposite state (see re-) + velare "to cover, veil," from velum "a veil" (see veil (n.)). Related: Revealed; revealer; revealing. Meaning "display, make clear or visible, expose to sight" is from c. 1500.
<a href="https://www.etymonline.com/word/revealing">Etymology of revealing by etymonline</a>
Harper, D. (n.d.). Etymology of revealing. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/revealing