D&C 38

The Prophet Joseph Smith was told in the early years of the Church -

"...now I show unto you a mystery, a thing which is had in secret chambers, to bring to pass even your destruction in process of time, and ye knew it not..." (Doctrine and Covenants Section 38:13)

The Lord knew that Satan would do all in his power to thwart the "marvelous work and a wonder" that had just begun.

President Joseph F. Smith said that -

"...the hatred of the wicked always has and always will follow the Priesthood and the Saints. The devil will not lose sight of the power of God vested in man—the Holy Priesthood. He fears it, he hates it, and will never cease to stir up the hearts of the debased and corrupt in anger and malice towards those who hold this power, and to persecute the Saints, until he is bound." (In Journal of Discourses, 19:24.)

He Lord then said -

"And again, I say unto you that the enemy in the secret chambers seeketh your lives." (Doctrine and Covenants Section 38:28)

This has never changed from then to now form both the a temporal and spiritual point of view. But with that, the Lord provides this great promise -

"...but if ye are prepared ye shall not fear." (Doctrine and Covenants Section 38:30)

In His preface to the Doctrine and Covenants the Lord explained -

"Prepare ye, prepare ye for that which is to come..." (Doctrine and Covenants Section 1:12)

For -

"...the arm of the Lord shall be revealed; and the day cometh that they who will not hear the voice of the Lord, neither the voice of his servants, neither give heed to the words of the prophets and apostles, shall be cut off from among the people." (Doctrine and Covenants Section 1:14)

To prepare is to hear or take heed to the voice of the Lord and His servants -

For He has declared -

"...whether by mine own voice or by the voice of my servants, it is the same." (Doctrine and Covenants Section 1:38)

This doesn't mean the valiant saints, those that prepare by taking heed to the prophets and apostles, will not be experience affliction or persecution, but they will not fear. Elder Bruce R. McConkie said in general conference -

“Nor are the days of our greatest sorrows and our deepest sufferings all behind us. They too lie ahead. We shall yet face greater perils, we shall yet be tested with more severe trials, and we shall yet weep more tears of sorrow than we have ever known before. . . .

The way ahead is dark and dreary and dreadful. There will yet be martyrs; the doors in Carthage shall again enclose the innocent. We have not been promised that the trials and evils of the world will entirely pass us by.

If we, as a people, keep the commandments of God; if we take the side of the Church on all issues, both religious and political; if we take the Holy Spirit for our guide; if we give heed to the words of the apostles and prophets who minister among us—then, from an eternal standpoint, all things will work together for our good.

Our view of the future shall be undimmed, and, whether in life or in death, we shall see our blessed Lord return to reign on earth. We shall see the New Jerusalem coming down from God in heaven to join with the Holy City we have built. We shall mingle with those of Enoch’s city while together we worship and serve the Lord forever.” (In Conference Report, Apr. 1980, pp. 98–100; or Ensign, May 1980, pp. 71, 73.)

The Lord concludes this revelation with -

"...I give unto you a commandment, that every man, both elder, priest, teacher, and also member, go to with his might, with the labor of his hands, to prepare and accomplish the things which I have commanded.
41 And let your preaching be the warning voice, every man to his neighbor, in mildness and in meekness.
42 And go ye out from among the wicked. Save yourselves. Be ye clean that bear the vessels of the Lord." (Doctrine and Covenants Section 38:40 - 42)