Arguing from the past in Philippians 2:12

Continuing with Paul's important exhortation to the Philippians in 2:12-13, "so then, my beloved, just as you have always obeyed, not as in my presence only, but now much more in my absence, work out your salvation with fear and trembling; for it is God who is at work in you, both to will and to work for His good pleasure."

We looked some at the "following-support" to Paul's exhortation "work out your salvation ...", which is the text of 2:13.  But before the exhortation are the words from the beginning of the verse as above, which people often skip.  This is the tail-end of what brings Paul to the exhortation.  Why does he bring up their past obedience?  Playing on their heart-strings?  Emoting?  No, although he loves them dearly, and loved them when they had met, and they always did what he said while he was with them.  These two chapters to this point are filled with some of the most amazing expressions of warmth of heart, plus theology intertwined, ever written.  Does "so then, my beloved, just as you have always obeyed, not as in my presence only, but no much more in my absence" add nothing to the meaning of his exhortation?  Of course it adds.  What does it add?

1. Paul wants them to consider their past time with him and all they participated in while he was with them.  

2.  Why was he not with them now?  He was in prison.  He's writing  a letter to those who he loves like crazy, from prison, saying over and over how great it was for them to have participated with him in this and that together.  How great was that?  

3.  While he's in prison, he wants something to be "much more." Paul's love makes him want to turn their shared, obedient participation with him in the past, into a quantity argument about the future.  He wants them to accept this quantity argument from him, that goes from their past obedient participation with him, toward  a "much more" version in the future.

4.  Why does Paul have the temerity to ask this, besides due to his love for them wanting the best?  What makes him want a "much more"?  Because although he's absent from them, he can remind them of God not being absent from them.  A greater than Paul, who is among them as he can't be, gives him the temerity to exhort like this.