Philippians 2:12-13

Therefore, my beloved, as you have always obeyed, so now, not only as in my presence but much more in my absence, work out your own salvation with fear and trembling, 13 for it is God who works in you, both to will and to work for his good pleasure.

(Paul doesn't tell us to "work out" anyone else's salvation. Darby (par. 5) points out that Paul is emphasizing this working out in his absence. In other words, he was concerned that the Philippians continue to do the working out of their salvation even when he was not there. So many times we are focused on the things of God when there is someone around us to encourage us and push us onward in our walk. But when that person leaves, especially if that person has a dynamic personality, we tend to not be as enthusisastic or as motivated in learning about the things of God and figuring out their application in our life. When this happens, we have to ask ourselves if we were focused on God because of the person or because of God Himself. I know that there have been times in my life when my walk has been more a result of the people around me than of my own inward motivation. At those times, the things I would do and the ways I would think when no one else was around were an indicator that I was not where I needed to be. I needed to come to the point where I saw the value for myself in living a Christian life. Part of our spiritual growth is coming to the point where we take responsibility for our walk with God and "do it" whether there is anyone else around or not. In my experience, this is an ongoing activity--a sanctification thing. As I grow, the Lord shows me areas that I need to change. This follows the model of learning. At first I am unaware of the area the Lord would have me change. Then, as He leads me through life experiences that point it out, I become aware of the area, but I don't truly see the need for change. Later, after He brings me through more experience, I see the need for change, but struggle to change. As I grow in the Lord, the struggle diminishes, but I'm not sure that it ever truly goes away. I think that's why Paul said that he didn't consider himself to have arrived, but he continually pressed on toward the mark (Philippians 3:14). It's at this point that the parallel of sanctification to the learning model breaks down. Sanctification has to be an ongoing thing if we are going to bring every thought captive in obedience to Christ (2 Corinthians 10:5-6). We never get to the point where we can consider ourselves "capable" (i.e., to have arrived) and if we ever reach the point where we have forgotten from whence we have come, then we probably haven't learned what we need and are not truly sanctified.)