“Preach the Truth as if you had a million voices. It is silence that kills the world.”
quoted in [LifeSite, The heart of the Catholic Church's current crisis is the abandonment of law and doctrine - LifeSite, 2022-06-07, 2022-05-05, https://www.lifesitenews.com/opinion/the-heart-of-the-catholic-churchs-current-crisis-is-the-abandonment-of-law-and-doctrine/]
Variant versions:
I see the world is rotten because of silence … speak the truth in a million voices. It is silence that kills. (quoted at 0:23 of [Randall Terry, The Silence That Kills, 2022-06-07, 2020-10-19, 23:29, https://www.youtube.com/watch?v=ql2ncPIgui0])
Original Italian: Oimé, non più tacere! Gridate con centomiglia di lingue. Veggo che, per lo tacere, el mondo è guasto, la Sposa di Cristo è impalidita ( Lettera 16, "A uno grande prelato" http://www.clerus.org/bibliaclerusonline/it/eki.htm#q)
lit.: "O alas, be silent no more! Shout with a hundred thousand tongues. I see that, through silence, the world is broken, the Bride of Christ is impaled"
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Catherine of Siena 3
Italian Dominican saint 1347–1380Related quotes

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Glenn Beck
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Fox News
2009-05-06
Beck rants about "power grab," claims "they are going to silence voices like mine"
Media Matters for America
2009-05-06
http://mediamatters.org/mmtv/200905060038
2000s, 2009

“The day will come when our silence will be more powerful than the voices you strangle today.”
Cited in: Kenneth G. Alfers (1993) America's second century: readings in United States history since 1877. p. 43