In "Doctrinal Discussion" Jason Lindahl writes:
Although the practice of referring to the church as a family existed long before the Gaithers, their song “The Family of God” clearly shows that the Church is a group of people who are connected by a common heritage. Each member of this family bears the marks of their Father — even God. And while each member is unique, the stress in the Church is upon the qualities members have in common because they are in a very real sense related to God. In this metaphor, the emphasis is upon the connectedness of the members of the Church. The Church is called the Bride of Christ. The context is still family, but the emphasis now shifts to the relationship between each member and their Lord, Jesus Christ. Marriage highlights the love that each church member feels for Jesus, and also the intimacy of that relationship. As beautiful and fulfilling as marriage is, Ephesians 5 seems to suggest that it is just a foretaste of the Christian's relationship with Jesus. When the Church is referred to as the Body of Christ, the emphasis is back on the inter-relatedness and dependence of the members of the Church. This metaphor highlights the two dimensions of church relationships. But this metaphor also places primary focus on the fact that Jesus is the Head of the Church — the chief executive officer. When things happen in an organization calling itself a church that are not directed by Jesus, that organization is losing its qualification to be called a church. A metaphor for the Church that comes from the animal world is the flock. Sheepherders are unanimous in their assessment that sheep are helpless, dependent animals. They often do foolish things that require the shepherd to undo, or else the sheep will die. Sheep must be led to places of food, drink, and shelter. This metaphor emphasizes the submission of the Christian to the Lord. The plant kingdom also provides a metaphor to communicate the meaning of the Church. In John 15, Jesus referred to Himself as the vine, and individual Christians are the branches. Just as no power tool can do its job unless it is connected to a power source, so Christians become impotent and ultimately will perish without being connected to Christ. The final metaphor comes from the field of architecture. The church is the building of God. The Bible makes it clear that Jesus is the foundation, the cornerstone, and the door of this building. Peter pointed out that Christians are merely the stones that make up the building. These stones are held in place by the mortar of the Spirit.
Source: Building Christian Relationships: Adult Teacher's Insights, page 50.