Demons can only do what God has permitted. There are saints who were attacked by demons…and this was with God’s permission, but the attack was to make them closer to God and to give them sanctifying grace…but none were put in danger of losing their lives, I think.
Among saints attacked are St. Gemma Galgani, Padre Pio, St. John Vianney, Catherine of Sienna.
Here is a book recommendation…The Rite by Matt Baglio.
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