1 Corinthians 2:1-7 NLT
 When I first came to you, dear brothers and sisters, I didn’t use lofty words and impressive wisdom to tell you God’s secret plan.  For I decided that while I was with you I would forget everything except Jesus Christ, the one who was crucified.  I came to you in weakness-timid and trembling.  And my message and my preaching were very plain. Rather than using clever and persuasive speeches, I relied only on the power of the Holy Spirit.  I did this so you would trust not in human wisdom but in the power of God.  Yet when I am among mature believers, I do speak with words of wisdom, but not the kind of wisdom that belongs to this world or to the rulers of this world, who are soon forgotten.  No, the wisdom we speak of is the mystery of God-his plan that was previously hidden, even though he made it for our ultimate glory before the world began.
What is the mystery of God?
What the Apostle Paul is writing about is Jesus Christ. He is the mystery of God revealed in human flesh. Humanly speaking, the message of the cross is nonsense and doesn’t make sense, but that’s where the experience of faith comes in. In what seems like foolishness to humanity, lies the wisdom of God. Jesus Christ was crucified for our sins so that we might have spiritual life, a life free from the confines of human wisdom and free to live for the glory of God!