Why do men fear this work? (Brigham Young

All the world are ready to tell you that this work is not of God. Kings, princes, dukes, lords, and other great men of the earth are all combined in this testimony. Why do they fear this work, if it is the work of men? The very sound of it carries conviction to all the inhabitants of the earth—a conviction that it is ordained of God. Were this not so, you would not see it contended against by the priests in the pulpit, who are bitter against it, and are most vigilant in circulating all manner of falsehood concerning it, picking up the sayings of corrupt, debased, abandoned characters to swell their catalog of lies against it, which they publish throughout the world. All this would sleep, if this work was not of God. They would never think enough of it to say one word about it. But they are pricked by the conviction of its truth when they hear the sound of it. When false reports go out against Joseph Smith and his brethren, against the Book of Mormon, and the kingdom of God, a conviction goes with them to the hearts of the people that this is the work of the Almighty. Were this not so, we should not have been persecuted—we should not have been driven as we have been.

Brigham Young, Journal of Discourses 8:315-16

See also Acts 5:38-39