In the Book of Mormon, the prophet Alma gave the following discourse on the topic of justice and mercy:
Alma 42
CHAPTER 42
Mortality is a probationary time to enable man to repent and serve God—The Fall brought temporal and spiritual death upon all mankind—Redemption comes through repentance—God Himself atones for the sins of the world—Mercy is for those who repent—All others are subject to God’s justice—Mercy comes because of the Atonement—Only the truly penitent are saved. About 74 B.C.
1 And now, my son, I perceive there is somewhat more which doth worry your mind, which ye cannot understand—which is concerning the justice of God in the punishment of the sinner; for ye do try to suppose that it is injustice that the sinner should be consigned to a state of misery.
2 Now behold, my son, I will explain this thing unto thee. For behold, after the Lord God sent our first parents forth from the garden of Eden, to till the ground, from whence they were taken—yea, he drew out the man, and he placed at the east end of the garden of Eden, cherubim, and a flaming sword which turned every way, to keep the tree of life—
3 Now, we see that the man had become as God, knowing good and evil; and lest he should put forth his hand, and take also of the tree of life, and eat and live forever, the Lord God placed cherubim and the flaming sword, that he should not partake of the fruit—
4 And thus we see, that there was a time granted unto man to repent, yea, a probationary time, a time to repent and serve God.
5 For behold, if Adam had put forth his hand immediately, and partaken of the tree of life, he would have lived forever, according to the word of God, having no space for repentance; yea, and also the word of God would have been void, and the great plan of salvation would have been frustrated.
6 But behold, it was appointed unto man to die—therefore, as they were cut off from the tree of life they should be cut off from the face of the earth—and man became lost forever, yea, they became fallen man.
7 And now, ye see by this that our first parents were cut off both temporally and spiritually from the presence of the Lord; and thus we see they became subjects to follow after their own will.
8 Now behold, it was not expedient that man should be reclaimed from this temporal death, for that would destroy the great plan of happiness.
9 Therefore, as the soul could never die, and the fall had brought upon all mankind a spiritual death as well as a temporal, that is, they were cut off from the presence of the Lord, it was expedient that mankind should be reclaimed from this spiritual death.
10 Therefore, as they had become carnal, sensual, and devilish, by nature, this probationary state became a state for them to prepare; it became a preparatory state.
11 And now remember, my son, if it were not for the plan of redemption, (laying it aside) as soon as they were dead their souls were miserable, being cut off from the presence of the Lord.
12 And now, there was no means to reclaim men from this fallen state, which man had brought upon himself because of his own disobedience;
13 Therefore, according to justice, the plan of redemption could not be brought about, only on conditions of repentance of men in this probationary state, yea, this preparatory state; for except it were for these conditions, mercy could not take effect except it should destroy the work of justice. Now the work of justice could not be destroyed; if so, God would cease to be God.
14 And thus we see that all mankind were fallen, and they were in the grasp of justice; yea, the justice of God, which consigned them forever to be cut off from his presence.
15 And now, the plan of mercy could not be brought about except an atonement should be made; therefore God himself atoneth for the sins of the world, to bring about the plan of mercy, to appease the demands of justice, that God might be a perfect, just God, and a merciful God also.
16 Now, repentance could not come unto men except there were a punishment, which also was eternal as the life of the soul should be, affixed opposite to the plan of happiness, which was as eternal also as the life of the soul.
17 Now, how could a man repent except he should sin? How could he sin if there was no law? How could there be a law save there was a punishment?
18 Now, there was a punishment affixed, and a just law given, which brought remorse of conscience unto man.
19 Now, if there was no law given—if a man murdered he should die—would he be afraid he would die if he should murder?
20 And also, if there was no law given against sin men would not be afraid to sin.
21 And if there was no law given, if men sinned what could justice do, or mercy either, for they would have no claim upon the creature?
22 But there is a law given, and a punishment affixed, and a repentance granted; which repentance, mercy claimeth; otherwise, justice claimeth the creature and executeth the law, and the law inflicteth the punishment; if not so, the works of justice would be destroyed, and God would cease to be God.
23 But God ceaseth not to be God, and mercy claimeth the penitent, and mercy cometh because of the atonement; and the atonement bringeth to pass the resurrection of the dead; and the resurrection of the dead bringeth back men into the presence of God; and thus they are restored into his presence, to be judged according to their works, according to the law and justice.
24 For behold, justice exerciseth all his demands, and also mercy claimeth all which is her own; and thus, none but the truly penitent are saved.
25 What, do ye suppose that mercy can rob justice? I say unto you, Nay; not one whit. If so, God would cease to be God.
26 And thus God bringeth about his great and eternal purposes, which were prepared from the foundation of the world. And thus cometh about the salvation and the redemption of men, and also their destruction and misery.
27 Therefore, O my son, whosoever will come may come and partake of the waters of life freely; and whosoever will not come the same is not compelled to come; but in the last day it shall be restored unto him according to his deeds.
28 If he has desired to do evil, and has not repented in his days, behold, evil shall be done unto him, according to the restoration of God.
29 And now, my son, I desire that ye should let these things trouble you no more, and only let your sins trouble you, with that trouble which shall bring you down unto repentance.
30 O my son, I desire that ye should deny the justice of God no more. Do not endeavor to excuse yourself in the least point because of your sins, by denying the justice of God; but do you let the justice of God, and his mercy, and his long-suffering have full sway in your heart; and let it bring you down to the dust in humility.
31 And now, O my son, ye are called of God to preach the word unto this people. And now, my son, go thy way, declare the word with truth and soberness, that thou mayest bring souls unto repentance, that the great plan of mercy may have claim upon them. And may God grant unto you even according to my words. Amen.
This sermon of Alma to his son Corianton covers the basis of the justice of God and that through the atonement of Christ the plan of mercy is also brought about. In this sermon Alma asks the question, Can mercy rob justice? His answer is, "No! not one whit". In the Book of Mormon we are also taught that that the atoning sacrifice had to be an infinite and eternal sacrifice.
Alma 34:8-16
8 And now, behold, I will testify unto you of myself that these things are true. Behold, I say unto you, that I do know that Christ shall come among the children of men, to take upon him the transgressions of his people, and that he shall atone for the sins of the world; for the Lord God hath spoken it.
9 For it is expedient that an atonement should be made; for according to the great plan of the Eternal God there must be an atonement made, or else all mankind must unavoidably perish; yea, all are hardened; yea, all are fallen and are lost, and must perish except it be through the atonement which it is expedient should be made.
10 For it is expedient that there should be a great and last sacrifice; yea, not a sacrifice of man, neither of beast, neither of any manner of fowl; for it shall not be a human sacrifice; but it must be an infinite and eternal sacrifice.
11 Now there is not any man that can sacrifice his own blood which will atone for the sins of another. Now, if a man murdereth, behold will our law, which is just, take the life of his brother? I say unto you, Nay.
12 But the law requireth the life of him who hath murdered; therefore there can be nothing which is short of an infinite atonement which will suffice for the sins of the world.
13 Therefore, it is expedient that there should be a great and last sacrifice, and then shall there be, or it is expedient there should be, a stop to the shedding of blood; then shall the law of Moses be fulfilled; yea, it shall be all fulfilled, every jot and tittle, and none shall have passed away.
14 And behold, this is the whole meaning of the law, every whit pointing to that great and last sacrifice; and that great and last sacrifice will be the Son of God, yea, infinite and eternal.
15 And thus he shall bring salvation to all those who shall believe on his name; this being the intent of this last sacrifice, to bring about the bowels of mercy, which overpowereth justice, and bringeth about means unto men that they may have faith unto repentance.
16 And thus mercy can satisfy the demands of justice, and encircles them in the arms of safety, while he that exercises no faith unto repentance is exposed to the whole law of the demands of justice; therefore only unto him that has faith unto repentance is brought about the great and eternal plan of redemption.
I think what this all means is that to bring about the bowels of mercy in the face of justice, a fallen sacrifice would not do. It had to be a lamb without blemish and spot. It had to be a being who was without sin and of an eternal nature. I think that Jesus, being a perfect being, sacrificed himself for sin so that the sacrifice would be a complete and eternal injustice. A lamb without blemish and spot could not deserve one iota of the punishment, suffering, and death that he suffered. It was a total injustice in the eyes of God our Heavenly Father. Because of the great injustice of the suffering of the Christ, an eternal recompense for his pain, suffering and death was a necessity and became the just thing for the Father to do. Not only for the pain, suffering and death but to the extent that he suffered. Christ suffered for the sins of all the world. His recompense should extent to the extent of that suffering. Jesus great recompense was to be able to grant mercy unto the repentant sinner and to overcome original sin. It would still be unjust for God to allow unrepentant sinners into the kingdom of heaven. Heaven would not be heaven if it were a sinful place. Repentance became a key requirement for mankind to receive the grace and mercy of Jesus Christ. Granting Jesus the power to forgive sins of the repentant soul was an act of justice on the part of the Father to Jesus who was a complete and innocent victim of this life who never deserved any of the pain, suffering and death he bore. Thus mercy became an act of justice and could not rob justice. It needed to be a sacrifice of a perfectly innocent and just being. An infinite and eternal sacrifice.