God, the supreme Lord and King of the whole world, has ordained civil authorities to be under him and over the people, for his own glory and the public good. For this purpose he has armed them with the power of the sword, to defend and encourage those who do good and to punish evildoers (Ro 13:1-4).
Christians may lawfully accept and carry out the duties of public office when called to do so. In performing their office they must especially maintain justice and peace (2Sa 23:3; Ps 82:3-4), according to the wholesome laws of each kingdom or other political entity. To carry out these duties they are authorized now under the New Testament to wage war in just and necessary situations (Lk 3:14).
Because civil authorities are established by God for the purposes stated, we should submit in the Lord to them in everything lawful that they require. We should submit not only for fear of punishment but also for the sake of conscience (Ro 13:5-7; 1Pe 2:17). We ought to make requests and prayers for kings and everyone in authority, so that under their rule we may live a quiet and peaceful life in all godliness and honesty (1Ti 2:1-2).