D&C 122 - 124

While in prison, the Prophet suggests "...for your consideration the propriety of all the saints gathering up a knowledge of all the facts, and sufferings and abuses put upon them by the people of this State;
2 And also of all the property and amount of damages which they have sustained, both of character and personal injuries, as well as real property;
3 And also the names of all persons that have had a hand in their aoppressions, as far as they can get hold of them and find them out." (Doctrine and Covenants Section 123:1 - 3)

"...and to take statements and affidavits; and also to gather up the libelous publications that are afloat;
5 And all that are in the magazines, and in the encyclopedias, and all the libelous histories that are published, and are writing, and by whom, and present the whole concatenation of diabolical rascality and nefarious and murderous impositions that have been practised upon this people—"
(Doctrine and Covenants Section 123:4 - 5)

For the purpose -

"That we may not only publish to all the world, but present them to the heads of government in all their dark and hellish hue, as the last effort which is enjoined on us by our Heavenly Father, before we can fully and completely claim that promise which shall call him forth from his hiding place; and also that the whole nation may be left without excuse before he can send forth the power of his mighty arm." (Doctrine and Covenants Section 123:6)

Because -

"...there are many yet on the earth among all sects, parties, and denominations, who are blinded by the subtle craftiness of men, whereby they lie in wait to deceive, and who are only kept from the truth because they know not where to find it—" (Doctrine and Covenants Section 123:12)

Because of such are under -

"an iron yoke...a strong band...the very handcuffs, and chains, and shackles, and fetters of hell."
(Doctrine and Covenants Section 123:8)

It then becomes our -

" imperative duty that we owe to God, to angels, with whom we shall be brought to stand, and also to ourselves, to our wives and children..." (Doctrine and Covenants Section 123:7) and "not only to our own wives and children, but to the widows and fatherless, whose husbands and fathers have been murdered under its iron hand..." (Doctrine and Covenants Section 123:9) and "also it is an imperative duty that we owe to all the rising generation, and to all the pure in heart—" (Doctrine and Covenants Section 123:11)

Therefore, we are commanded -

"...that we should waste and wear out our lives in bringing to light all the hidden things of darkness,[as] they are truly manifest from heaven...with great earnestness." (Doctrine and Covenants Section 123:13 - 14)

"...Let no man count them as small things; for there is much which lieth in futurity, pertaining to the saints, which depends upon these things...Therefore, dearly beloved brethren, let us cheerfully do all things that lie in our power; and then may we stand still, with the utmost assurance, to see the salvation of God, and for his arm to be revealed."
(Doctrine and Covenants Section 123:15 - 17)