James E. Faust taught,

“We need not become paralyzed with fear of Satan’s power. He can have no power over us unless we permit it. He is really a coward, and if we stand firm, he will retreat. The Apostle James counseled: “Submit yourselves therefore to God. Resist the devil, and he will flee from you” (James 4:7). He cannot know our thoughts unless we speak them. And Nephi states that “he hath no power over the hearts” of people who are righteous (See 1 Nephi 22:26).”

(James E. Faust, CR, Oct. 1987, p. 43)