Jesus' Primary Theme: The Kingdom of God

As long as anyone could remember, the land was being overrun by powerful foreign kingdoms every few hundred years or so: first Babylon, then Greece, then Rome. If the pattern was going to continue, the land was due for another conquest… just when Jesus arrived on the scene with these words.

When a massive army comes and overruns your homeland, you know that some serious life-rearrangement is in order. And this is what Jesus is telling us. The Kingdom of Heaven -- the Kingdom of God -- is coming. It is going to radically change your life -- whether you like it or not!

...but it is often very difficult to change our way of thinking! 
Matthew 4:17 "From that time on, Jesus began to preach, '[Change your way of thinking]: the Kingdom of God is near!'" (also Mark 1:15)
Matthew 6:33 "But seek first his kingdom and his righteousness, and all these things will be given to you as well." 
Matthew 13:44 "The kingdom of heaven is like treasure hidden in a field. When a man found it, he hid it again, and then in his joy went and sold all he had and bought that field.