God has made no attempt to clarify the Kingdom by giving us the details or a description. The Kingdom is presented in ambiguous terms and clouded in mystery. Of course there are the parables and certain examples and comparisons to identify the kingdom, but the mystery is not removed so all who hear can understand. Especially if we determine to preach a clear word that all may understand. If we don't preach a clear word so people understand, the Devil comes immediately and steals the word away.
Understanding is absolutely essential for the word to take root and bear fruit.
However, it is not possible to preach the Kingdom so all will understand. It is clear then why the Kingdom can only be preached by the anointing of the Holy Spirit and with the power and demonstration of the Spirit. The Kingdom can only be understood by those whom the Holy Spirit gives revelation. Some have ears to hear but still cannot hear. Some have eyes to see but still cannot see.