The kingdom of heaven is like a farmer. Or maybe it's like a man who had two sons. Or a woman baking bread. Or a fisherman with his nets.
Jesus' teachings are very down-to-earth - literally. Where we have some sort of expectation that a Great Teacher should transcend this world, take us elsewhere in our thoughts, Jesus resolutely refused that path. Whenever the conversation turned to great abstract principles, we could expect one thing: a parable was following. His parables did more than illustrate the lessons. He spoke as if the holy belongs in this world.
According to centuries upon centuries of Christian teaching, this is the ultimate meaning of Jesus' life, death, and resurrection: that the holy belongs in this world. Holiness is not meant to be an abstract. It is not meant to be an otherworldly thing. It is not located uniquely in monasteries or other outposts of rejecting this world. It is located firmly within this world. There is nothing important about holiness that cannot be described in terms of growing seed, vineyards, and wedding feasts.
Some see the parables as a kind of mystery. But the parables also seem to be instances of incarnation: in a parable, a general principle takes on reality, takes on flesh and blood, and walks in this world in a recognizable form. So the direction of Christ's teaching is not to take this world as raw material that needs to be turned into the finished product of an abstraction. The direction of Christ's teaching is the opposite: to take the raw material of abstraction and turn it into the finished product of a God-filled reality. The ultimate understanding of God's truth does not take the form of a properly-classified entry in our theological system; it touches our world.
When an expert in the Law of Moses tested Jesus, asking after the most important commandment, he got his answer: Love the Lord your God, and the second like it: love your neighbor as yourself. But when the lawyer asked who was his neighbor, he found out the truth about that great commandment. That great commandment was not great because it could take a leading place in the catalog in the law-books. It was great because it was the one that could live in us and move us to help the traveler we meet along the way. It is a great commandment because it takes the vital core of the image of God -- that is, love -- and places it back inside us. Love is the nature of God. For this reason, love is the greatest of the virtues, and love is the greatest of the commandments. When we love our neighbor, the word of God is incarnated in us and our actions. When Jesus repeats his refrain, "The kingdom of God is like ...", every down-to-earth story he tells invites us to fill in the rest of the story with our own lives, our own children, and our own neighbors, to see it all as part of the kingdom of heaven.