Righteousness Through Faith in Christ (v. 1-11)
Paul says once again that we gain righteousness through faith in Christ and not through our own works. He discusses how he used to be very powerful and was perfect from the perspective of the law, but he gave it all up to follow christ. In the last couple verses, he says he will do whatever he can to share the sufferings of Christ and become like him in death so that he can attain the resurrection from the dead.
This is more glorifying faith. What you do doesn't matter, what you think does. Following the law doesn't help you, just having faith. That is all that really matters. I guess the implication is that once you have faith you will do good things anyway, so that's why following the law doesn't matter. I'm not sure this bears out in reality though, people being good and people having faith in Christ seem to be independent variables.
This last bit is interesting, he wants to share the sufferings of Christ so he can be resurrected. So ultimately his motivation is selfish. I guess most of what we do is ultimately selfish on some level, but something about the way it is spelled out here makes me a bit uneasy. Also, he talks of being resurrected from the dead. This feels fundamentally different to me than our common conception of going to heaven. "resurrection from the dead" sounds to me like coming back to life here on earth, not living on in heaven.
Straining Toward the Goal (v. 12-21)
I am not perfect, but I am eternally striving toward perfection. Join me in this way of thinking.
This message I like quite a lot. It fits into the message of being humble that we have seen a few times. Don't assume you are perfect, work to better yourself.
v.18-19 Many are enemies of the cross, their end is destruction, their god is their belly, they glory in their shame with their minds set on earthly things.
This doesn't seem quite as bad as some verses in the past, I think because it starts with people who are "enemies of the cross" and then follows that they are bad, rather than starting with them simply being not Christian and then saying they are bad. I still think this is a bad message, it basically says that people who are not like us are evil. It sets people up to hate those not like themselves. This is obviously a bad thing.
For the overview post (If you think I should add or remove stuff from this list please let me know, I think it would make good conversation)
3:12 I'm not perfect, but I'm always striving for perfection
"Not that I have already obtained this or am already perfect, but I press on to make it my own, because Christ Jesus has made me his own."
3:8 Everything other than Christ is worthless
"Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ"
3:9 Faith is a virtue [thanks ReasonBeing]
"and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith"
3:18-19 People who are not like us are evil
"For many, of whom I have often told you and now tell you even with tears, walk as enemies of the cross of Christ. Their end is destruction, their god is their belly, and they glory in their shame, with minds set on earthly things."