A document produced in 1647 still has wise words for us today, particularly #s 1 and 4...
1. God, the supreme Lord and King of all the world, hath ordained civil magistrates to be under Him, over the people, for His own glory, and the public good: and, to this end, hath armed them with the power of the sword, for the defense and encouragement of them that are good, and for the punishment of evil doers. (Romans 13:1-4, I Pet. 2:13-14)
2. It is lawful for Christians to accept and execute the office of a magistrate, when called thereunto: in the name of managing whereof, as the ought especially to maintain piety, justice, and peace, according to the wholesome laws of each commonwealth; so for that end, they may lawfully, now under the new testament, wage war upon just and necessary occasion. (ie, magistrates may wage and fight a just war. Prov 8:15-16, Rom 3: 1-2,4, Psalm 2:10-12, I Tim. 2:2, Psalm 82: 3-4, 2 Sam 23:3, I Pet. 2:13, Luke 3:14, Rom 13:4, Matt 8:9-10, Acts 10:1-2)
3. Civil magistrates may not assume to themselves the administration of the Word and sacraments; or the power of the keys of the kingdom of heaven, or, in the least, interfere in the matters of faith. Yet, as nursing fathers, it is the duty of the civil magistrates to protect the church of our common Lord, without giving preference to any denomination of Christians above the rest, in such a manner that all ecclesiastical persons whatever shall enjoy the full, free, and unquestioned liberty of discharging every part of their sacred functions, without violence or danger....[2 Chron 26:18, Matt 18:17, Matt 6:19, Heb 5:4, John 18:36, ad so on)
4. It is the duty of people to pray for magistrates, to honor their persons, to pay tribute or other dues, to obey their lawful commands, and to be subject to their authority, for conscience' sake. Infidelity or difference in religion does not void the magistrates just and legal authority, nor free the people from their due obedience to them: from which ecclesiastical persons are not exempted, much less hath the Pope any power and jurisdiction over them in their dominions, or over any of their people; and least of all, to deprive them of their dominions, or lives, if he shall judge them to be heretics, or upon any pretence whatsoever. (1 Pet 2:17, Rom 13:6-7, Rom 13:5, Titus 3:1, I Pet 2:13-14, 16, Rom 13:1, Acts 25:9-11, 2 Pet 2:1, 10-11, Jude 8-11)