There are three verses in Acts that state Paul spent most of his time teaching the Gospel of the Kingdom. If the gentiles who built their little worldly empire of an institutionalised religion and church, had included those writings which must have existed, rather than convenient epistles that corresponded with how to built a religion, there might not be any division seen between Paul and Jesus' teachings, both being focused on the Kingdom. The Gentiles were the ones guilty of the separation, not only of the two men but between Gentile and Jew even though we were to be as one.
Acts 19:8 He (Paul) went into the synagogue, and spake boldly for the space of three months, disputing and persuading the things concerning the Kingdom of God
Acts 28: 23 And when they had appointed him a day, there came many to him into his lodging; to whom he expounded and testified the kingdom of God, persuading them concerning Jesus, both out of the law of Moses, and out of the prophets, from morning till evening. 24 And some believed the things which were spoken, and some believed not.
Acts 28: 30 And Paul dwelt two whole years in his own hired house, and received all that came in unto him, 31 Preaching the kingdom of God, and teaching those things which concern the Lord Jesus Christ, with all confidence, no man forbidding him.
Acts 19:8 He (Paul) went into the synagogue, and spake boldly for the space of three months, disputing and persuading the things concerning the Kingdom of God
Acts 28:23 He expounded and testified the kingdom of God, persuading them concerning Jesus, both out of the law of Moses, and out of the prophets