1 Corinthians 2:1-5

1When I came to you, brothers, I did not come with eloquence or superior wisdom as I proclaimed to you the testimony about God.[a] 2For I resolved to know nothing while I was with you except Jesus Christ and him crucified. 3I came to you in weakness and fear, and with much trembling. 4My message and my preaching were not with wise and persuasive words, but with a demonstration of the Spirit's power, 5so that your faith might not rest on men's wisdom, but on God's power.

What is there to know really, other than "Jesus Christ and Him crucified"? All of the world's philosphies and self help--Stephen Covey, Dale Carnegie, Dr. Phil, Oprah-- while they can provide genuinely helpful band-aids sometimes, and may even include some of the true elemnts of Christianity, they all eventually fail us by themselves because they lack the foundational element-- "Jesus Christ and Him crucified".

Jesus is a person, who still lives today, who has paid for any and every sin we can ever dream of, no matter how heinous. Not only that, he is our God, whom we can worship and entrust our lives to. He will never go even an inch away from us, because He lives in us. He loves us and uses His infinite power to veto anything that could happen to us that does not contribute to our best interest. He knows us a lot better than we know ourselves. He knows our spouses, kids, friends and even our enemies a lot better than we know them. He has called us, given us a purpose and many different ways that we can creatively serve Him. If we can understand all of these things (and much more) that make up "Jesus Christ and Him crucified", there is really nothing else that we need to know.