Why is it rejected? For the most part, in order to receive a gift, a person has to recognize the source of the gift (God) and the purpose of the gift (to help them). Yet, the wicked take to the truth to be hard.
...the guilty taketh the truth to be hard, for it cutteth them to the very center. (1 Nephi 16:2)They don't recognize truth. They don't recognize the hand of God. They don't desire things that are right, and therefore don't see the offered gift as something that will help at all--at least not help them get what they want, which is almost always physically impossible.
...ye have sought all the days of your lives for that which ye could not obtain; and ye have sought for happiness in doing iniquity, which thing is contrary to the nature of that righteousness which is in our great and Eternal Head. (Helaman 13:38)We see our gift thrown away, our sacrifice returned void. Many times, we even find ourselves receiving railing and accusation of evil in return for our unwavering example of exactly what Christ would do in our position: delivering freely what was acquired with great cost for no purpose other than to bless another.
The personal loss is not nearly as painful as the sure knowledge of the painful path the individual you tried to help has just delivered themselves to: unnecessary suffering whose only purpose is to break them down and humble them. Sometimes, in fact, the trajectory of this person's entire life has now been downgraded, and they have lost out permanently on the full blessings God desired to bestow upon them.
The absolute pinnacle of sorrow you can feel for someone is to realize beyond a shadow of a doubt that they are beyond reason. In such a state, absolutely nothing you can do can help them realize things as they really are. You are completely powerless to help them. The scriptures have many names for this state: reprobate, past feeling, ripe in iniquity, etc. They all mean the same thing. In common parlance, we unfortunately assume that this condition has something to do with what a person is doing. For example, "oh he is a drug addict, therefore he is a wicked person." Or, "she is a prostitute, therefore the case is hopeless." As near as I could tell, Jesus did quite well with the types of people we regularly write off because of some sin that we judge to be particularly repugnant. He ate with these people, he blessed these people, and they repented and came to him in droves.
The quality of being ripe in iniquity is not about what you do at all. It's about what you don't do. It's about your lack of ability to recognize and accept truth.
God sends higher truth to all his children. When they reject it, he downshifts and teaches lower truth, but still higher than what they possess. When they reject everything, there is nothing left for him to send.
But behold, this people had rejected every word of God, and they were ripe in iniquity; and the fulness of the wrath of God was upon them; (1 Nephi 17:35)
Wo unto them that turn aside the just for a thing of naught and revile against that which is good, and say that it is of no worth! For the day shall come that the Lord God will speedily visit the inhabitants of the earth; and in that day that they are fully ripe in iniquity they shall perish. (2 Nephi 28:16)I once asked God why he would destroy this and all other countries in our day instead of in the past. After all, there isn't much we are doing today that hasn't been done for a long time. For instance, we have been murdering the innocent through unjust war and abortion for decades. Why punish us for it now?
The answer was two part. First, the main difference between our actions now and our actions then is that we are openly flaunting our wickedness as if it were virtue (see Isaiah 3:9). Behavior once limited to private indulgence due to public recognition of it as sinful behavior is paraded in public today as the achievement of an advanced society.
However, the main answer was this: destruction isn't usually (and won't be in our case) about specific actions. Rather surprisingly, it is merely about our societal approach to reason. Although many fashion their own god who arbitrarily rewards those who obey him and punishes those who disobey him, the God I have come to know is not arbitrary. His instructions guide us toward or away from natural consequences. In this case, destruction is the only option when an environment exists that does not permit the purpose of our lives: to learn to discern between good and evil.
Maybe you don't think the ability to reason is so important. After all, what does it matter if someone simply "agrees to disagree"? However, one's ability to consider both sides of an issue is tantamount to their ability to listen to God.
For intelligence cleaveth unto intelligence; wisdom receiveth wisdom; truth embraceth truth; virtue loveth virtue; light cleaveth unto light; (D&C 88:40)If someone can't accept something minor that is true, there is no way they can accept something major that is true. It is all connected. Any rejection of truth has an effect on a persons ability to accept saving truth, whether the rejected truth itself is saving or not.
Reason is the way, and the only way, we learn truth. Some might think this is an overstatement that discounts learning by revelation. God does not impose truth on us, not by other people, and not be the Spirit. He reasons with us. Find a place in the scriptures where God tells something to someone. He gives instruction. He explains consequences. He reasons.
The tools in D&C 121 are the only tools God has. When the first ones fail to work, his only choice is to send destruction so that others who are born will not be forced into an environment where reason cannot function. An individual who is incapable of reason is incapable of growing closer to God. They are effectually cut off from him, and there is nothing that can bring them back.
The purpose of life is to learn to discern between good and evil. When a critical mass of the inhabitants of a land (or the world, in our digitally connected, world-is-flat society) refuse to reason, it creates an environment where the upcoming generation's ability to reason is poisoned.
Surely Jehovah’s hand has not become too short to save,
nor his ear dull of hearing!
2 It is your iniquities that separate you from your God;
your sins hide his face, so that he does not hear you. 3 For your palms are defiled with blood,
your fingers with iniquity;
your lips speak guile, your tongue utters duplicity.
4 None calls for righteousness;
no one sues for an honest cause.
They rely on empty words, deceitfully spoken; they conceive misdeeds, they beget wickedness.
5 They hatch vipers’ eggs and spin spiders’ webs; whoever eats of their eggs dies,
and if any is smashed, there emerges a serpent.
6 Their cobwebs are useless as clothing;
their fabrications are worthless for covering themselves.
Their works consist of wrongdoing; they manipulate injurious dealings.
7 Their feet rush after evil;
they hasten to shed innocent blood.
Their thoughts are preoccupied with mischief; havoc and disaster follow in their wake.
8 They are unacquainted with the way of perfection; integrity is not within their bounds.
They have made crooked their paths; none who treads them knows peace.
9 Therefore redress remains far from us
and righteousness is unable to reach us.
We look for light, but there prevails darkness;
for a glimmer of hope, but we walk amid gloom.
10 We grope along the borders like the blind; we flounder like those without eyes.
We stumble at noon as in the dark of night; in the prime of life we resemble the dead.
11 We grumble like bears, all of us; we moan incessantly like doves.
We expect justice when there is none;
we look for salvation, but it eludes us.
12 For our transgressions before you have multiplied; our sins testify against us.
Our offenses are evident; we perceive our iniquities: 13 willfully denying Jehovah,
backing away from following our God, perversely planning ways of extortion,
conceiving in the mind and pondering
14 And so redress is compelled to back away,
and righteousness to stand at a distance; truth stumbles in the public place
and uprightness cannot enter.
15 When integrity is lacking,
they who shun evil become a prey.
Jehovah saw that there was no justice, and it displeased him.
16 When he saw it, he wondered
why there was no man, no one who would intercede.
So his own arm brought about salvation for him; his righteousness rallied to his cause.
17 He put on righteousness as a breastplate
and made salvation the helmet on his head;
he clothed himself with vengeance for a garment and wrapped himself in fury as in a robe.
18 According to what they deserve, he will repay them: wrath upon his adversaries,
reprisals upon his enemies;
to the isles he will render retribution.
19 From the west men will fear Jehovah Omnipotent,a and from the rising of the sun his glory.
For he will come upon them like a hostile torrent impelled by the Spirit of Jehovah.
20 But he will come as Redeemer to Zion,
to those of Jacob who repent of transgression, says Jehovah.
21 As for me, this is my covenant with them, says Jehovah: My Spirit which is upon you and my words which I have placed in your mouth shall not depart from your mouth, nor from the mouth of your offspring, nor from the mouth of their offspring, says Jehovah, from now on and forever. (Isaiah 59, Gileadi Translation)