Do everything without grumbling or arguing, so that you may be blameless and pure, children of God without blemish though you live in a crooked and perverse society, in which you shine as lights in the world by holding on to the word of life so that on the day of Christ I will have a reason to boast that I did not run in vain nor labor in vain. – Philippians 2:14-16
Verses 14-16 doesn’t have any conjunction or connector that would tell us how to relate this passage logically from the preceding verses. The immediate context seems to imply that this is an inference from or at least a way of working out your salvation.
For the following reasons:
Now how does “not grumbling” would result to blamelessness?
If you can control your tongue and not stumble from it, then you can control and bridle your whole body and not stumble from it(James 3:1-2). It means you’re already perfect. Sin of grumbling is the most hard to overcome, because it flows from the dissatisfaction of the heart. Scripture says “out of the abundance of the heart the mouth speaks”. If we treasure in our hearts earthly things and will never be satisfied by it for eternity, our hearts will just abound with complaints hence grumble against God. Therefore if we don’t grumble anymore, that only means we’re perfectly satisfied in God.
Do we really need to strive to attain perfection? Am I being a legalist if I pursue that?
Yes, we need to strive because Paul did and we are to imitate him as he imitate Christ. No, we are not being legalist nor perfectionist. Paul strived to make it his own because he already belongs to Christ(Philippians 3:7-21)
Therefore the way to work out is by doing all things without grumbling until the completion of our salvation, namely the attainment of blamelessness at the coming of Christ. And the grounds for this command is that God is working in us both the willingness and ability to look for the interest of others which is a means to a murmur free life.
My confident hope is that I will in no way be ashamed but that with complete boldness, even now as always, Christ will be exalted in my body, whether I live or die. For to me, living is Christ and dying is gain. – Philippians 1:20-21