The rule for all ages seems to be that the most bitter enemies the prophets and kingdom of God will have are those who once embraced the faith and later were filled with an evil spirit and left. How strange it is that people leave the churches of the world by the hundreds of thousands every year to embrace the restored gospel with no feelings of bitterness toward those churches they have left!
Yet when people leave the Church of Jesus Christ, frequently they cannot leave it alone, but must wear out their lives in bitter attacks against it. As Joseph Smith attested, there is no neutrality where the Church and kingdom of God are concerned. (See Joseph Fielding McConkie and Robert L. Millet, Sustaining and Defending the Faith, chapter 1.)
“Worse Than Though They Had Never Known These Things”
Joseph Smith stated in 1834: “From apostates the faithful have received the severest persecutions. Judas was rebuked and immediately betrayed his Lord into the hands of His enemies, because Satan entered into him. There is a superior intelligence bestowed upon such as obey the Gospel with full purpose of heart, which, if sinned against, the apostate is left naked and destitute of the Spirit of God, and he is, in truth, nigh unto cursing, and his end is to be burned.
When once that light which was in them is taken from them, they become as much darkened as they were previously enlightened, and then, no marvel, if all their power should be enlisted against the truth, and they, Judas like, seek the destruction of those who were their greatest benefactors. What nearer friend on earth, or in heaven, had Judas than the Savior? And his first object was to destroy Him.” (Teachings, p. 67.)