Are we to preach the kingdom of heaven or to preach Christ crucified as Paul instructs us?
There is no difference.
Paul told the Ephesians, "And indeed, now I know that you all, among whom I have gone preaching the kingdom of God, will see my face no more" (Acts 20:25). And he told the Corinthians, "but we preach Christ crucified, to the Jews a stumbling block and to the Greeks foolishness" (I Corinthians 1:23). To preach one is to the preach the other because both are a part of the Gospel.
Thank you for your response. I have a person who was and is telling me it is wrong to preach Christ crucified, that I should be preaching the kingdom of heaven. But I think you can cover all things by Christ crucified, whereas preaching the kingdom of God you must still come back to what happened at the Cross. Please point out any fallacies that I may have as a lay person in my reasoning. Thank you.
Clearly your friend is wrong since the core of the Gospel is the evidence that Jesus died and arose. "For I delivered to you first of all that which I also received: that Christ died for our sins according to the Scriptures, and that He was buried, and that He rose again the third day according to the Scriptures" (I Corinthians 15:3-4).
But you are both making similar mistakes. You are seeing an "only" in statements where none exist. Christianity is not taught by teaching only that Jesus was crucified. Nor is it taught by only speaking about the kingdom and its nature. Where in either of those two topics will you discuss how fathers are supposed to raise their children (Ephesians 6:4), yet that is a part of the Gospel message.
Paul said, "Therefore I testify to you this day that I am innocent of the blood of all men. For I have not shunned to declare to you the whole counsel of God" (Acts 20:26-27). When we don't teach the whole message, we are guilty before God because a partial message is a misleading message. "The entirety of Your word is truth, And every one of Your righteous judgments endures forever" (Psalms 119:116).
Thank you! I will take that to my core, it is the whole gospel!