"Christ rules over all spheres of authority whether angelic or human (Matt. 28:18; 1 Pet. 3:22). His kingdom in a direct sense is the church, the body over which He is the head, governing it by His word and Spirit (Eph. 1:22, 23). As for the state: it is not related to the kingdom of God as it was in the Old Testament. The sword is not to be used to enforce Christ's kingdom (John 18:36), but Christ uses secular authority to maintain civil peace and order, and commands His disciples to submit to rulers (Matt. 22:21; Rom. 13:1-7). Christians seek in every sphere of life to do His will, reminding themselves and others that all are accountable to Christ as Judge, whatever their position in life may be (Matt. 25:31; Acts 17:31; Rom. 2:16; 2 Cor. 5:10)." -R.C. Sproul