Be poor in spirit --> you shall receive kingdom of heaven
See also Romans 8:17, D&C 84:38, D&C 56:18
Poor in spirit means that we are spiritually dependant on God. It means we know our need for God.
Mourn --> you shall be comforted
Russell M. Nelson said, "The only way to take sorrow out of death is to take love out of life." (The Gateway We Call Death, p. 22-24)
Be meek --> you shall inherit the earth (see Articles of Faith v. 10)
“…meekness has a metabolism that actually requires very little praise or recognition-of which there is usually such a shortage anyway.
“…Meekness also protects us from the fatigue of being easily offended. There are so many just waiting to be offended. They are so alerted to the possibility that they will not be treated fairly, they almost invite the verification of their expectations! The meek, not posted on such a fatiguing alert, find rest from this form of fatigue.
“…Bruising as the tumble off the peak of pride is, it may be necessary…Meekness enables us, after a tumble, to pick ourselves up but without putting others down blamefully.
“…The deserving and blessed meek will not only eventually inherit the earth, they will do so when this planet is really worth inheriting!”
“…If meek, we will place all we have on the altar of the Lord and will not ask for a receipt!” (Neal A. Maxwell, Meek and Lowly, pp. ix, 55, 57, 58, 95, 207)
Hunger and thirst after righteousness --> you shall be filled with the Holy Ghost
What would you do if you were literally dying of hunger and thirst? What if you were a mother or father of little children who needed food and water and who were going to die if they did not eat or drink? What would you do? I would imagine I would do just about anything to feed my family. Jean Valjean was so desperate that he stole bread to feed his family.
I can recall going outside to run for exercise one hot summer day. It may have been foolish of me to run out in the heat at the time, but I wasn't too concerned at the time. I was on the last stretch of the run and I was thirsty. I was not simply thirsty; rather I was deliriously thirsty. All I could think about was water. I was desperate. Thirst was my only motivation to get back home. Thirst is what drove me to finish that day.
Are we just as motivated to seek righteousness or are we passive? Jesus taught us to truly desire righteousness.
Be merciful --> you shall obtain mercy (at the judgment seat and in this life)
One of mercy's synonyms is forgiveness. I will never forget the last talk President Faust gave in General Conference (April 2007). It was perhaps the most emotional talk by a general authority I've seen.
We must have mercy and forgive if we are to live in peace. If we let revenge and hate decay our souls, our lives will indeed by hell. We can always choose to have mercy.
Be pure in heart --> you shall see God
Elder Wirthlin said the following, "To be without guile is to be pure in heart—an essential virtue of those who would be counted among true followers of Christ. He taught in the Sermon on the Mount, “Blessed are the pure in heart: for they shall see God” (Matt. 5:8; see also 3 Ne. 12:8). He revealed to the Prophet Joseph Smith that Zion is the pure in heart (see D&C 97:21) and that a house is to be built in Zion in which the pure in heart shall see God (see D&C 97:10–16).
"If we are without guile, we are honest, true, and righteous. All of these are attributes of Deity and are required of the Saints. Those who are honest are fair and truthful in their speech, straightforward in their dealings, free of deceit, and above stealing, misrepresentation, or any other fraudulent action. Honesty is of God and dishonesty of the devil; the devil was a liar from the beginning. Righteousness is living a life that is in harmony with the laws, principles, and ordinances of the gospel." (Joseph B. Wirthlin, “Without Guile,” Ensign, May 1988, 80).
President Kimball said the following, "Zion is 'every man seeking the interest of his neighbor, and doing all things with an eye single to the glory of God.' (D&C 82:19.) As I understand these matters, Zion can be established only by those who are pure in heart, and who labor for Zion, for 'the laborer in Zion shall labor for Zion; for if they labor for money they shall perish.' (2 Ne. 26:31.)" (Spencer W. Kimball, “Becoming the Pure in Heart,” Ensign, May 1978, 79) He then went on to outline how the Church can become pure in heart.
Be a peacemaker --> you shall be called a child of God
Elder Nelson said, "Now, as members of The Church of Jesus Christ of Latter-day Saints, what does the Lord expect of us? As a Church, we must “renounce war and proclaim peace.” (D&C 98:16) As individuals, we should “follow after the things which make for peace.” (Romans 14:19) We should be personal peacemakers. We should live peacefully—as couples, families, and neighbors. We should live by the Golden Rule. We have writings of the descendants of Judah as now merged with writings of the descendants of Ephraim. (Ezek. 37:16-19; 2 Nephi 3:12) We should employ them and expand our circle of love to embrace the whole human family. We should bring divine love and revealed doctrines of restored religion to our neighbors and friends. We should serve them according to our abilities and opportunities. We should keep our principles on a high level and stand for the right. We should continue to gather scattered Israel from the four corners of the earth and offer the ordinances and covenants that seal families together forever. These blessings we are to bring to people of all nations." (Russell M. Nelson, “‘Blessed Are the Peacemakers’,” Ensign, Nov 2002, 39)
Be persecuted --> you shall receive the kingdom of heaven and the reward therein
“I am like a huge, rough stone rolling down from a high mountain; and the only polishing I get is when some corner gets rubbed off by coming in contact with something else, striking with accelerated force against religious bigotry, priestcraft, lawyer-craft, doctor-craft, lying editors, suborned judges and jurors, and the authority of perjured executives, backed by mobs, blasphemers, licentious and corrupt men and women—all hell knocking off a corner here and a corner there. Thus I will become a smooth and polished shaft in the quiver of the Almighty.” (Teachings of the Prophet Joseph Smith, sel. Joseph Fielding Smith, Salt Lake City: Deseret Book Co., 1938, p. 304.)
What the Beatitudes boil down to is one word: humility.