Nowhere is this plainer than the way the apostle describes how "God decided through the foolishness of our proclamation to save those who believe" (1 Cor 1:20). This does not mean that preaching is foolish, but that it seems foolish to rational hearers. In fact, to them it is absurd nonsense. The world has never understood the paradox of God's wisdom. That the message about Jesus' death on a cross and apparent defeat is the clearest way God expresses who He is, and what He has done for the world. Here "God so loved the world that he gave his one and only son (John 3:16). "
When you preach the paradox of the cross you are on the front edge of foolishness. Yet this very act is God's wisdom and power. By ordinary people, God confronts the world's wisdom with his own. Never straight forward but gloriously powerful, this is the mystery of preaching. Anyone who preaches commits to an awesome task of telling out a different kind of wisdom.
How this truth rebukes the presumption that lies behind truism 1. Most preachers regard themselves as above average. How dare we think that we can measure how "good" our preaching is. Rather, God seeks people who are foolishlessly powerful in his service. Heralds of mystery need to be humble and overawed by the high calling.
I like how James Earl Massey sums it up:
Mystery is something whose utter strangeness and stubborness forever resist all attempt on our part to domesticate it, dominate, define it or dismiss it. Life is a mystery! Death is a mystery! The incarnation is a mystery! The resurrection of Jesus from death is a mystery! Our life on this planet involves us in mystery! The story of God's gracious dealings with us through grace involves us in mystery! We who preach are stewards of the mysteries of God. What we offer and extend through preaching can be experienced but it is more wonderful - filled with what arouses wonder and awe- than we can fully explain. (Stewards of the Story, WJK: 2006, page 4).