Paul shows his analytical tendencies in this passage. It logically follows that IF we have been risen with Christ, THEN we should seek those things that are heavenly. Our position should be reaffirmed by our practice. Too bad we seem to have to convince ourselves that this is how things work, because it doesn't. While this is how things should work, we still must actively seek those things which are above and simultaneously shun the baser things of earth.
Verse 10: Paul recognized the completion of a cycle in this verse. God creates man in His Image. Man sins and by the time Seth is born scripture says he was born in the image of his father, Adam. Now, in Christ, the image has been restored to a godly one.
Verse 11: Consider the radical nature of this statement. This is not the age of tolerance. This is the age of Jewish separation and legalism. Greek intellectual superiority. Slaves being considered less-than-men. Paul says that in Christ everyone is equal. There is no difference because all are condemned naturally and all can be redeemed by Christ.
Not only is there no difference in God's eyes, but now there should be no difference in your eyes as well. We are to be a community of believers with Christ in common. Since Christ should be everything to us, we, in essence, have all things in common. This attitude should reign in all that we do one with another, that the brotherhood of believers be shown to be the most important earthly institution--established by God Himself.
Verse 16: I find it interesting that Paul urges the believers to teach and admonish with songs before he instructs to sing songs. The songs were used as an affirmation of doctrine in the assembly, they were the liturgy. Without Bibles, the lyrics of the songs would be used for teaching core beliefs concerning Christ. Most of Paul's letters are believed to be sections of songs used to commemorate Christ's core actions.
Verse 17 sums up Paul's argument concerning social relationships, whatever situation you find yourself in treat it as though you were in that situation with the Lord. Christ should be such a large part of our existence that we cannot function without Him at the forefront of our consideration.