Philippians 2:12

Therefore, my dear friends, as you have always obeyed—not only in my presence, but now much more in my absence—continue to work out your salvation with fear and trembling,

(v12, NIV)

What does it mean to work out your salvation? How can work and salvation be positively correlated with one another? I mean, that's how us as humans think, but it seems opposite to the gospel.

For it is by grace you have been saved, through faith—and this not from yourselves, it is the gift of God— not by works, so that no one can boast.

(Ephesians 2:8-9, NIV)

Clearly we see here that it is not by works. We are saved by grace through faith in Jesus Christ, not by anything we can work toward to earn.

What good is it, my brothers, if a man claims to have faith but has no deeds? Can such faith save him? Suppose a brother or sister is without clothes and daily food. If one of you says to him, "Go, I wish you well; keep warm and well fed," but does nothing about his physical needs, what good is it? In the same way, faith by itself, if it is not accompanied by action, is dead.

(James 2:14-17, NIV)

Here in James, it seems somewhat contrary to the gospel as well. If we have faith we need deeds. Without deeds, faith is dead. If you notice, it's not saying that we are saved because of our deeds. Rather, deeds prove the faith. Without deeds, it means that you never really have faith. Many of us try to do the math in our own heads and link things together. For example, we know that we are saved by grace through faith in Jesus Christ. Therefore, we need faith to be saved. Then we learn that faith without deeds is dead. Since salvation requires faith and faith requires deeds, we jump to conclude that salvation requires deeds. That is true in a sense, but it doesn't mean deeds are the saving. Rather, those who are saved have deeds, but they are not saved because of their deeds.

so, what does it mean to work out our salvation with fear and trembling? Well, the doing is the proving, not the saving. If you know that you are saved, continue to prove it by your deeds. Since faith without deeds is dead, continue to live in humble surrender to the Lord Jesus Christ. Fear God.

Therefore, since we are surrounded by such a great cloud of witnesses, let us throw off everything that hinders and the sin that so easily entangles, and let us run with perseverance the race marked out for us. Let us fix our eyes on Jesus, the author and perfecter of our faith, who for the joy set before him endured the cross, scorning its shame, and sat down at the right hand of the throne of God. Consider him who endured such opposition from sinful men, so that you will not grow weary and lose heart.

(Hebrews 12:1-3, NIV)

The author of Hebrews describes our life as a race. If this is a race, those who partake in it run to win. Most people don't enter a race to walk the whole way. Run the race. Run the race with perseverance. Continue to run and run hard.

We are followers of the Lord Jesus Christ. We are graciously saved by grace through faith in Jesus Christ. Just because we are saved, it doesn't mean we can simply indulge in sin and its okay. It is not a one-time thing. It's not like one of those shots you get from the doctor. You take a shot once and you're covered for 10 years or for the rest of your life or something. That is not how it works with God. Do you love God who saved you? Continue to serve him. Your continual service to him will prove that you were saved. However, those who weren't truly saved will not persevere. Work out your salvation with fear and trembling. Fear God.