As a missionary, the author encountered a Christian who was particularly annoyed by the Mormons and their assertion that salvation was the responsibility of the individual and not a free gift. He just couldn't believe that it was necessary to work out your own salvation with fear and trembling (Philippians 2:12). As with most critics, he did not know or understand his own scriptures. He had attributed to Mormonism what is clearly taught by Paul to the Phillippians. Ironically, it is the writings of Paul which have so confused Christianity on just this issue.
Many will testify that "work" is the right word to describe the process of our spiritual struggles for salvation. Nephi groaned under the weight of his sins (2 Nephi 4:19) and Enos had to wrestle with his (Enos 1:2). Alma described being born again only after wading through much tribulation, repenting nigh unto death (Mosiah 27:28). Expecting salvation without work is like expecting a college degree without attending any classes; it is expecting to reap where one has not sown.
David O. McKay
"An outstanding doctrine of the Church is that each individual carries the responsibility to work out his own salvation, and salvation is a process of gradual development. The Church does not accept the doctrine that a mere murmured belief in Jesus Christ is all that is necessary. A man may say he believes, but if he does nothing to make that belief or faith a moving power to do, to accomplish, to produce soul growth, his professing will avail him nothing. To work out one's salvation is not to sit idly by dreaming and yearning for God miraculously to thrust bounteous blessings into our laps. It is to perform daily, hourly, momentarily, if necessary, the immediate task or duty at hand, and to continue happily in such performance as the years come and go, leaving the fruits of such labors either for self or for others to be bestowed as a just and beneficent Father may determine.
"I am not unmindful of the scripture that declares: 'by grace are ye saved through faith; and that not of yourselves: it is the gift of God.' (Eph. 2:8.) That is absolutely true, for man in his taking upon himself mortality was impotent to save himself. When left to grope in a natural state, he would have become, and did become, so we are told in modern scripture, 'carnal, sensual, and devilish, by nature.' (Alma 42:10.) But the Lord, through his grace, appeared to man, gave him the gospel or eternal plan whereby he might rise above the carnal and selfish things of life and obtain spiritual perfection. But he must rise by his own efforts and he must walk by faith." (Conference Report, Apr. 1957, p. 7)
Heber C. Kimball
"Jesus says, 'Work out your salvation as it is my will to work within you.' Then, again, we are commanded to work out our salvation with fear and trembling. All that hinders us and prevents us progressing faster, and going on from one step to another even as it was with our Father, even the Father and God pertaining to this earth, is our lack of confidence in the Almighty, and our slothfulness in the things of God. Joseph the Prophet said that our heavenly Father went on from one degree of knowledge to another until he obtained the knowledge that made him God. So also will it be with us, we shall have to advance from one degree of faith to another until we get that knowledge that will prepare us for exaltation in our Father's kingdom. But we must first prove ourselves in this state of probation, then we rise from step to step till we reach that position that is promised to the people of God." (Journal of Discourses, vol. 9, p. 371)