act of faith

American  

noun

1. an act that demonstrates or tests the strength of a person's convictions, as an important personal sacrifice.

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act of faith British  

noun

1. Christianity an act that demonstrates or tests a person's religious beliefs

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act of faith Idioms  

1. Behavior that shows or tests a person's religious or other convictions, as in Rock climbing with a new, inexperienced partner was a real act of faith. The term is a translation of the Portuguese auto da fé, which referred to the sentencing and execution of heretics (often by burning at the stake) during the Inquisition, when punishing heresy was thought to constitute an assertion of faith. In modern times it is used for more benign circumstances. [Early 1700s]

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Example Sentences

See Examples For:

act of faith

You could keep it if the tenant/landlord doesn’t have an answer or, if you feel generous, donate it to charity or — as an act of faith — leave it for the cleaner.

From MarketWatch ● Aug. 11, 2026

"I have been witnessing miracles of healing through the years because of this act of faith."

From Barron's ● Apr. 3, 2026

The Catechism of the Catholic Church teaches that Mary’s consent—“Let it be done.”—was a free, active and essential act of faith that allowed the Incarnation to occur.

From The Wall Street Journal ● Mar. 18, 2026

“It was such an act of faith, because, you know, we’re in the middle of this incredible disaster.”

From Los Angeles Times ● Dec. 8, 2025

And so he builds, because what is building, and rebuilding and rebuilding again, but an act of faith?

From "Zeitoun" by Dave Eggers