Justification means “to be pardoned from punishment for sin and declared guiltless. A person is justified by the Savior’s grace through faith in him. This faith is shown by repentance and obedience to the laws and ordinances of the gospel. Jesus Christ’s atonement enables mankind to repent and be justified or pardoned from punishment they otherwise would receive” (Guide to the Scriptures, “Justification, Justify”).
Elder Dallin H. Oaks instructed us that the Book of Mormon teaches that “salvation does not come by keeping the commandments alone. ‘By the law no flesh is justified’ (2 Nephi 2:5). Even those who serve God with their whole souls are unprofitable servants (see Mosiah 2:21). Man cannot earn his own salvation.
“The Book of Mormon teaches, ‘Since man had fallen he could not merit anything of himself’ (Alma 22:14). ‘There can be nothing which is short of an infinite atonement which will suffice for the sins of the world’ (Alma 34:12; see also 2 Nephi 9:7; Alma 34:8–16). ‘Wherefore, redemption cometh in and through the Holy Messiah; … he offereth himself a sacrifice for sin, to answer the ends of the law’ (2 Nephi 2:6–7). And so we ‘preach of Christ … that our children may know to what source they may look for a remission of their sins’ (2 Nephi 25:26)” (in Conference Report, Oct. 1988, 78; or Ensign, Nov. 1988, 67).