O how great the goodness of our God, who prepareth a way for our escape from the grasp of this awful monster; yea, that monster, death and hell[!]
2 Nephi 9:10
There's a second major reason I believe in the Gospel as taught by the Church of Jesus Christ of Latter-day Saints. I believe that, when fully understood, the Gospel encompasses all truth and organizes it into the most wonderful, merciful, and just view of the nature of God, the nature of man, and the purpose of life and existence. I don't claim to be a theologian or expert on world religions, but I am familiar with the basics of most major world religions, and I honestly believe that Mormonism holds the most truth. If I thought another religion or philosophy had more truth, I would join that other religion. So far, I haven't found one.
In this blog post, I won't include scriptural support for my writing; that would make this entry far too long. I will delineate the basic essentials of LDS doctrine.
To understand this all-encompassing plan, you have to know our true relationship to God. This knowledge was lost soon after the death of the Apostles in the primitive Christian Church and restored through Joseph Smith.
God is our Father in a quite literal sense; we are of the same divine race as He is. We are gods in embryo. God is not some kind of ethereal, supernatural entity that is categorically different and far removed from us. God, angels, and man are all of the same divine race at different stages of progression. God has fully developed and matured, and His entire purpose in regards to us is to see us grow to be as He is.
A basic tenet of existence is that things grow and evolve. Although we don't know much about the primal origins of our spirits, we do know that there was a time of growth before being born on Earth. Just as babies are born in mortality and grow to maturity, passing through different stages of development, so too are all of God's children born as children and must grow and develop naturally. The final goal is to attain to God's status and become, with Christ, an heir of God's kingdom.
Another important fact is that God has a corporeal body. It is different from our mortal bodies, but our bodies were fashioned after Christ's, which was fashioned after God the Father's. That physical body encompasses both crude element and spirit. All spirit is actually a type of incredibly fine matter, undetectable by our current methods of observation.
Before coming to the Earth, we didn't have physical bodies. Although we are children of God, we are still very young and at an early stage of our development. Before living on Earth, we had bodies composed entirely of spirit, not element. Because we didn't have bodies, there are certain things we couldn't do (such as move and act) that we naturally wanted to do. Eventually we reached a point where we couldn't continue to progress unless we obtained a body. There are certain things that simply cannot be experienced or achieved without a physical body; things that are vital to continued growth to becoming as God is.
The problem is that having a body exposes a person to all sorts of temptations and afflictions. Receiving a body and living in it is a trial-and-error experience, and sometimes we make serious errors.
God is perfectly just. There is a certain order to the cosmos and God's nature that cannot be broken, or else He would cease to be God (for instance, He cannot lie). Because of that justice, he cannot allow anything that would disrupt that perfect order into His kingdom. Therefore, anything and anyone who breaks that perfect order is unfit to live with Him. Unfortunately, everyone who has lived has sinned to some degree and therefore fallen short of the perfect glory of God. That sin corrupts our souls and makes us unfit to return again to live with Him.
God knew that this would happen, and prepared a contingency plan. Jesus Christ was also with us before the world was created. Christ was another child of God who was much farther along the path than we were. Christ was chosen to be the Messiah (literally, the "anointed one") who would act as our Savior: if we would listen to Him and obey His commandments (which He would ensure were always possible to do), He would forgive us our sins, heal our souls, and help us return to live with God again.
One of the defining characteristics of God is agency: He can choose what He will do, thereby affecting the universe. It is by this principle of agency that He is able to organize the cosmos in such a way so as to produce conditions amenable to His children's growth. Because we are like Him, agency is also one of our defining characteristics. We get to choose what we will do, thereby choosing the consequences of our actions.
This mortal life has many purposes. One of those purposes is to act as proving grounds and see whether we will do everything that God requires of us. If we faithfully preform our God-given duties, we will have proven ourselves worthy of inheriting God's kingdom. We must be tested on the most primal level, so that the very core of our nature is revealed. If we remembered our lives before mortality, the proving process wouldn't work as needed. Therefore, there is a "veil of forgetfulness" that stops us from remembering our lives before mortality.
When you combine the natural difficulty of morality (with its temptations and afflictions) with human agency and the veil of forgetfulness, you have a recipe for potential disaster. Even with a Savior, many men and women would choose to reject the truth of God for various reasons. Some would even, after having been fully healed by Christ and brought into His presence again, reject God and thereby damn themselves eternally. A portion of humankind would be lost.
God made us aware of this fact before the Earth was created. We entered into this trial willingly, fully informed of the trials that awaited us. The fact that some would be lost, however, was alarming to a number of God's children. This created a division where Lucifer led a contingent of God's children in rebellion against God and Christ. At the center of the conflict was agency itself: Lucifer claimed that, if given the power, he could remove man's agency and force everyone to do good. That way, Lucifer claimed, every spirit would return to live with God and none would be lost. It is written that a "third part" of God's children sided with Lucifer. They lost the conflict, however, and were subsequently cast out of heaven into the Earth.
The story of Adam and Eve in the Garden of Eden is symbolic; it's not a literal history of the beginning of mankind. It is meant to convey to us the truths we need to believe to understand our place in the world and how we relate to God. According to that allegory, God created the Earth and the Garden of Eden and put Adam in the Garden. God gave Adam certain commandments that had to do with what to eat and not to eat (tree of life: good; tree of knowledge of good and evil: bad) and then created Eve. Adam and Eve were both innocent in the beginning, like little children, and didn't know the difference between good and evil. Adam relayed God's commandments to Eve, but Satan (or "adversary", as Lucifer was now known after his fall) tempted Eve and convinced her to take the fruit of the tree of knowledge of good and evil. After partaking of the fruit, she convinced Adam to partake as well and they both learned the difference between right and wrong.
As a result of transgressing God's command not to eat the fruit of the tree of knowledge of good and evil, Adam and Eve were expelled from the Garden of Eden. They began to have children and, after a time, angels appeared to Adam and taught him the Gospel of Jesus Christ: that Jesus Christ would be born into mortality, at some point, and live and die as a propitiation for Adam's transgression and the sins of all mankind.
The Gospel of Jesus Christ is simple, and is explained, by Christ, in 3 Nephi 27:13-21:
13 [T]his is the gospel which I have given unto you—that I came into the world to do the will of my Father, because my Father sent me.
14 And my Father sent me that I might be lifted up upon the cross; and after that I had been lifted up upon the cross, that I might draw all men unto me, that as I have been lifted up by men even so should men be lifted up by the Father, to stand before me, to be judged of their works, whether they be good or whether they be evil—
15 And for this cause have I been lifted up; therefore, according to the power of the Father I will draw all men unto me, that they may be judged according to their works.
16 And it shall come to pass, that whoso repenteth and is baptized in my name shall be filled; and if he endureth to the end, behold, him will I hold guiltless before my Father at that day when I shall stand to judge the world.
17 And he that endureth not unto the end, the same is he that is also hewn down and cast into the fire, from whence they can no more return, because of the justice of the Father.
18 And this is the word which he hath given unto the children of men. And for this cause he fulfilleth the words which he hath given, and he lieth not, but fulfilleth all his words.
19 And no unclean thing can enter into his kingdom; therefore nothing entereth into his rest save it be those who have washed their garments in my blood, because of their faith, and the repentance of all their sins, and their faithfulness unto the end.
20 Now this is the commandment: Repent, all ye ends of the earth, and come unto me and be baptized in my name, that ye may be sanctified by the reception of the Holy Ghost, that ye may stand spotless before me at the last day.21 Verily, verily, I say unto you, this is my gospel[.]
That, in a nutshell, is the plan of happiness: despite our sins, personal failures, and sadness in life we can be forgiven and healed through the mercy of God. That healing and forgiveness comes through following the commandments of Jesus Christ, who is our advocate with God.