When you read this, you can perceive my insight into the mystery of Christ,  which was not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit. (ESV)
The mystery of Christ being revealed is much bigger than you and I tend to realize. Generations of mankind did not understand this mystery. In fact, it is interesting to note that until the Holy Spirit revealed this truth to the Apostle Paul, even he did not understand it. As for a little background, the Apostle Paul, before he became a Christian, was one of the most highly educated of all the Jews. The book of Acts gives us some insight into Paul's background:
 “I am a Jew, born in Tarsus in Cilicia, but brought up in this city, educated at the feet of Gamaliel according to the strict manner of the law of our fathers, being zealous for God as all of you are this day. (ESV)
In Paul's time, instead of going to a school like Harvard or Yale, you were trained by a great Rabbi. That was the case for Paul. When he says that he was educated at the feet of Gamaliel he is claiming something that would have impressed the people of his day. He was a scholar of Scripture. He had all the knowledge that the men of his day could understand. And did all of that knowledge lead him to the revelation of the mystery of Christ? NO! He was persecuting the Church to death. It was not until the Holy Spirit opened his eyes that he was able to receive the revelation of the mystery of Christ.
There is something here for us. We have been given the Holy Spirit. Each one of us who has given our life to Jesus Christ has the Holy Spirit dwelling within us. As you seek to know more about the Lord Jesus Christ, read the Word of God, with the leading and direction of the Holy Spirit. The Holy Spirit is vital to our understanding anything.
The Holy Spirit is your helper. He will reveal to you the truth of Jesus Christ. Ask him to show you what you need to know. Give him authority in your life to lead you today.