4 When Christ, who is our life, is revealed, then you also will be revealed with Him in glory.
The "therefore" is "there for" the purpose of drawing us back to the thought of the previous verses - we were buried with Christ and raised to new life through His sacrifice and not through any human effort.
One of the biggest lessons I am learning is to seek the things above. The year started with having to put my dog to sleep, then the end of my Daddy's battle with cancer, and most recently a scare when it seemed that my husband's lymphoma was back. (It isn't!) God is teaching me that He will provide the manna I need for the day, and if I waste my time worrying over tomorrow's all I will receive is maggots! I am also more and more convicted about the vast amount of material things my family possesses and the fact that it is completely unbiblical to have this much "stuff" when others do not have their basic needs met.
We are called to walk through life on earth, not as secluded hermits but in the midst of the battle. We build and nurture relationships, lift each other up in the bad times, and celebrate the wonderful blessings of life. But through it all our hearts must be focused on Him, our treasures laid up in heaven, our time spent furthering His kingdom and not our own. When we set our minds on things above it not only prepares us for heaven, it gives meaning to our lives on earth.
Having a heavenly focus reminds us that no matter how dark the trial, the Light of the World is with us. Having a heavenly focus reminds us to see glimpses of heavens in the joys of this life. Having a heavenly focus turns our hearts to him with praise in the good times and the bad. We will spent eternity with Him in glory, and this life will seem less than a blink of an eye in comparison.
Finally, brethren, whatever is true, whatever is honorable, whatever is right, whatever is pure, whatever is lovely, whatever is of good repute, if there is any excellence and if anything worthy of praise, dwell on these things. - Philippians 4:8