God himself is in a community of three persons in one—the Father, Son, and Holy Spirit—who exist in perfect unity. So it is not surprising that from the beginning, God created us to be in community with one another. Genesis 2:18 states: "It is not good for man to be alone." This passage is often used in the context of marriage, but it also speaks to our fundamental need to connect with others in the human community. What is striking about this statement is that God makes it before the Fall. There's no sin yet and no disobedience; man is in perfect intimacy with God. And yet, God declares that man is alone and that it is not good.
Community is deeply grounded in the nature of God. It flows from who God is. Because he is community, he creates community. It is his gift of himself to humans. Therefore, the making of community may not be regarded as an optional decision for Christians. It is a compelling and irrevocable necessity, a binding divine mandate for all believers at all times.
When Jesus' ministry began, he called 12 disciples to be his primary relational and ministry community. Did Jesus need this motley crew to help him? Not really. But Jesus chose to love them, teach them, and pour himself into relationships with them, thereby creating the first "small group."
The apostles continued Jesus' model and formed a community of believers who loved God and loved one another. Despite incredible persecution and against all odds, this rag tag group of Jesus-followers launched small communities (i.e. church) that proclaimed the gospel and changed the world forever.