Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but how much more in my absence, work out your own salvation with fear and trembling. For it is God which worketh in you both to will and to do of his good pleasure. (Phil 2:12-13)
It is common for Evangelical critics of LDS soteriology (e.g., Ron Rhodes and Marian Bodine) to argue that Paul was addressing the internal conflicts in the Philippian church and was merely addressing the survival/salvation of the congregation, not a statement about individual salvation. In this way, Evangelicals attempt to empty this passage of its eternal dimensions and limit the discussion to working out one's salvation to working out their disputes. However, this ignores verse 16 which reads:
Holding forth the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither laboured in vain.
Here, Paul speaks of the final judgment ("the day of Christ"). Hence, all the fear and trembling that Paul encourages the Philippians to do is for the purpose of passing the judgment on that final day. If Paul finds that he has "laboured in vain," we know from other passages that the salvation of his hearers/readers is either in jeopardy or has yet to be determined (e.g., Gal 2:2; 2 Cor 6:1; 1 Thess 3:5). Even Paul does not think of himself as "eternally secure," as we see in 1 Cor 9:27-10:13).
As one Pauline scholar wrote on this passage, showing that Paul is teaching synergistic soteriology:
Finally, Phil 2:12-16, particularly verses 12-13, deserves a more thorough analysis. What does Paul mean by the phrase “with fear and trembling work out your own salvation” (2:12)? Some suggest that σωτηρια refers to the health and welfare of the corporate body of believers in Philippi, not final salvation from God’s wrath or eternal life in the next age. This sociological interpretation has been amply rebutted. Here, as in 1:28, σωτηρια refers to eschatological salvation as it usually does elsewhere in Paul’s letters.
What, then, does Paul mean by κατεργαζομαι? Paul uses the word eighteen other times with the meaning “to achieve, accomplish, do, bring about, produce, or create.” In this case, then, Paul exhorts the Philippians to bring about or achieve their own salvation. Considering all the passages discussed in this section, such a mandate and responsibility should come as no surprise. Why else would Paul exhort believers to be “pure and blameless,” or to “produce a harvest of righteousness,” or to be “blameless and innocent . . . without blemish” in light of the imminent day of Christ, unless he also believes that Christians themselves must work in order to be saved on that day. Κατεργαζομαι refers to a number of things, such as “live your life in a manner worthy of the gospel” (1:27), “standing for in one spirit, striving side by side with one mind for the faith of the gospel” (1:28), “do nothing from selfish ambition or conceit, but in humility regard others as better than yourselves” (2:3), “look not to your own interests but to the interests of others” (2:4), do all things without murmuring and arguing” (2:14), “holding fast to the word of life” (2:16), and so on. Christians themselves do these things, not God; they decide as an act of the will to obey or disobey Paul, the gospel, or God.
Believers do such things, however, not on their own strength alone. Paul says, “For God is the one who is working in you so that (you might) desire to work for (his) good pleasure” (2:13). God aids and inspires the believers to accomplish God’s purposes. Likewise, Paul testifies about himself:
Not that I have already obtained this or have already reached the goal; but I press on to make it my own, because Christ Jesus has made me his own. (Phil 3:12)
I can do all things through him who strengthens me. (Phil 4:13)
On the contrary, I worked harder than any of them—though it was not I, but the grace of God that is with me. (1 Cor 15:10)
In his autobiographical statements, sometimes Paul emphasizes his role in his endeavors (e.g., 2 Cor 11:23-29; Phil 2:16; 1 Thess 2:9), sometimes God’s grace. Paul views himself as neither “possessed” or controlled by the deity nor as constrained or overpowered; rather he is inspired. If one’s deeds rely solely upon God’s doing, then the logic of God’s commandments is lost and responsibility for one’s behaviour at the Last Judgment is moot. (Chris VanLandingham, Judgment and Justification in Early Judaism and the Apostle Paul [Peabody, Mass.: Hendrickson, 2006], 186-87)
This Evangelical "response" to the force of Phil 2:12-13 is as pathetic as it is driven by eisegesis.