Chapter 4 moves on to explore Man in the image of God, and our calling as Christian men to bear that image before a watching world. In Christ we are once again made children of God to fulfil role God gave to Adam as a rational and spiritual being who is God's regent for his glory.
There is one quotation which perhaps best sums up this chapter: "The single greatest issue of our lives is: revealing the glory of God to a sin darkened world so that he will be praised and lost sinners will be saved by coming to know the Lord."
He goes on to practically flesh this ought exhorting men to devote ourselves to strengthening our faith so that we can then strengthen others, serve in church, spiritually bless and encourage people and so on. We strengthen ourselves by making use of those things God has given us to that end: his word, prayer and the sacraments. So that we become more conformed to his image.
My one reservation is that I would like there to have been a greater emphasis on relationships - having stressed that man is to cultivate relationships in chapter 2 it is curiously missing from this chapter. Development of the strengthening of and by others would have been helpful, God gives us each other and the church to encourage one another, to work the gospel into one another's lives. Nevertheless it is still a chapter with much to challenge us.