Source: https://www.bertha-dudde.org/en/proclamation/4438
4438 Demonic influence on light bearers.... fight against truth....
September 21, 1948: Book 52
The demonic influence is particularly strong where the truth threatens to break through, and that is why you are often plagued by thoughts which these beings let flow towards you and which are intended to make you unfit to receive or pass on the truth. Light and shadow are always together, the battle of light against darkness always takes place, and the human being's will determines which forces will win the day. Where there is light, i.e. truth, the dark beings also crowd together to extinguish it, to displace truth through lies and error. And this has the effect that every spiritual work is made difficult for the bearers of light as soon as they themselves do not muster the strong will to be constantly active for God and His kingdom. Then a light bearer draws strength from God and can resist every influence from the demonic side, then he is stronger than that strength, then he has the spiritual light as a protective wall around him and can resist every influence, every wrong thought. The strength of will must never weaken, then even the demonic forces will have no effect. Yet a bearer of truth will always feel the proximity of these beings which fight against the truth insofar as the spiritual work is more difficult, that inhibitions and obstacles influence it and the human being must again and again request strength anew from God and thus join God ever more intimately if he does not want to become weak and leave victory to the demonic forces. Yet he will never remain without help, for once the light can be guided to earth there are countless beings of light ready to defend him, and anyone who has once offered his services to God will also find a faithful helper and advisor in Him Who will never abandon him to the enemy but protect him against his influence....
Amen
Translated by Doris Boekers