One of the mysteries of the English language finally explained.
1An act requiring or demonstrating (religious) faith.
2Specifically = "auto-da-fé". Also "†act of the faith". Now historical.
Early 16th century; earliest use found in William Tyndale (c1494–1536), translator of the Bible and religious reformer. From act + of + faith.
act of faith/ˌakt əv ˈfeɪθ/
In this article we explore how to impress employers with a spot-on CV.