Paul's introduction to this letter reminds the Christian Church of the importance of rejoicing in God's grace in Christ.  Though "predestination" often evokes annoyed looks of frustration and memories of overly-enthusiastic young men talking endlessly about it, verses four to six celebrate this blessing.  It's the source of our salvation.  We were chosen from eternity in Christ, which means that God is eternally acting for our salvation.  Though our will is not on par with God's, election doesn't nullify our will - we've been chosen to be conformed to Christ's image, which requires holy thoughts, words, and deeds.  The ultimate purpose of learning of God's electing grace is that we might bring Him glory.  God did not choose us due to anything He foresaw within us.  It was according to His own good pleasure, which means that He alone receives our thanks and praise.