Paul has chased a serious concern through his entire letter

So it is not surprising that near the end, he would present an the ultimate challenge of the Christian life
- in verse 16 Paul begins last segment of his central message
• what follows in chapter 6 is his concluding remarks and directions
- what we have in verses 16-25 is this chunk of scripture that tracks one theme
• Paul makes this clear by marking where it begins and ends
•it begins in verse 16, “walk by the Spirit,” and in ends in verse 25, “live by the Spirit”
◦ in scripture, framing a passage this way is common, and is referred to as an envelope structure or closing circle
◦ anyway, the literary structure reveals the heart of the passage–it’s one key point