The plan of mercy is the plan of salvation's answer to the law of justice. In the discussion of sin, law, and punishment, the law comes first. It is a principle as eternal as God himself. Its integrity must be preserved at all cost, for as soon as the law of justice is destroyed, so is God's divinity (v. 22). Against this seemingly unrelenting force, we place ourselves in a very precarious position when we sin. Without the plan of mercy, we would be like an ant under a falling anvil, waiting for our well-deserved, crushing punishment. The plan of mercy, fortunately intercedes. Boyd K. Packer said, "Through Him mercy can be fully extended to each of us without offending the eternal law of justice." (Dallin H. Oaks, The Lord's Way, p. 218) Remarkably, the plan of mercy simultaneously preserves the law and offers protection to the violator of the law.
Bruce R. McConkie
"Mercy is thus for the repentant, the faithful, the obedient, those who love and serve God. All other fail to escape the clutches of justice. 'Blessed are the merciful: for they shall obtain mercy.' (Matt. 5:7.) 'Be ye therefore merciful, as your Father also is merciful.' (Luke 6:36.) Salvation is the reward of those who conform to the plan of mercy. 'Surely goodness and mercy shall follow me all the days of my life: and I will dwell in the house of the Lord for ever.' (Ps. 23:6.)
"So infinite in scope is the plan of mercy that it applies to the living and the dead. Those who did not have the opportunity to subject themselves by repentance to the plan of mercy while in this life, but who would have done so had the opportunity been afforded them, will have their chance in the spirit world; they shall then be saved from the grasp of justice and, reaping the full blessings of mercy, shall go on to celestial reward.
"'There is never a time when the spirit is too old to approach God,' the Prophet said. 'All are within the reach of pardoning mercy, who have not committed the unpardonable sin, which hath no forgiveness, neither in this world, nor in the world to come. There is a way to release the spirits of the dead; that is by the power and authority of the priesthood -- by binding and loosing on earth. This doctrine appears glorious, inasmuch as it exhibits the greatness of divine compassion and benevolence in the extent of the plan of human salvation.' (Teachings, pp. 191-192.)" (Mormon Doctrine, p. 486)