The body of Christ, the church, is the life and mission of Christ the Savior in the world today. To look at the mission of the church is to look at the mission of Christ. In the suffering servant passages of Isaiah interspersed through chapters 42-61, we find a beginning description of who God's Christ would be when he came. The Christ is described there as a suffering servant rather than a regal earthly monarch. The definition of any community of God's people, local or otherwise, needs to be based upon this suffering servant image, this image of Christ.
Jesus encapsulated the prophecies of the Old Testament in his life and mission as the suffering servant of God. He was the Christ, the one whom God anointed by his Spirit. When he departed, he sent forth his power and authority upon his followers. He gave his disciples, the body of Christ, the power to continue his mission, to be him in the world. So his people are to be the suffering servant community. Therefore we should shape our understanding of the church on those Old Testament passages concerning the Christ who is to come.