The mention of God colors and lifts the matter of deference far above mere social rectitude, making it part of our preparation for His Kingdom. This charge addresses our overall responsibility to God and thus to human governing officials because Paul shows them to be God's agents (Romans 13). In this context, it is the king.
Our responsibility is stated as obeying the king because of our oath to God. An oath is a formal declaration to do or not do something. Synonyms include “vow,” “pledge,” “swear,” or “promise.” Oaths are serious business. In Matthew 5:33-37, Jesus counsels us not to swear at all because of our weakness in keeping them. In this particular case, one may even bear greater responsibility than normal because the oath is made to God.
This oath could be one of three possibilities. Exodus 24:7-8 shows Israel's pledge to obey God by keeping the Old Covenant:
Then [Moses] took the Book of the Covenant and read in the hearing of the people. And they said, “All that the LORD has said we will do, and be obedient.” And Moses took the blood, sprinkled it on the people, and said, “Behold, the blood of the covenant which the LORD has made with you according to all these words.”
The second oath is the covenant we have made with God to be obedient to Him. Jesus Himself says in Luke 14:26-27:
If anyone comes to Me and does not hate his father and mother, wife and children, brothers and sister, yes, and his own life also, he cannot be My disciple. And whoever does not bear his cross and come after Me cannot be My disciple.
Whether or not we fully grasped it, at the time of our baptism and laying on of hands, we were pledging our lives and activities to faithfulness to Jesus Christ.
The third possibility is the least likely to apply. It is swearing before a judge during a courtroom trial to tell the truth, the whole truth, and nothing but the truth “so help me God.” This used to be done with a raised right hand or with a hand on a Bible.
The sense of responsibility to obey God must be cultivated, despite the sometimes foolish, self-centered humans in between Him and us. Those people may have done something very damaging that directly affects us or someone we love. They may have spoken forcefully against God and His way. It is easy to feel oppressed by them because, in their unconversion, they have become enemies of God. Being self-controlled in such situations may even prove to be life-saving.
Giving deference is not a mere civil duty. Making the covenant with God and deferring to those in authority can become a difficult, sacred obligation. It becomes more difficult when we perceive their self-centeredness and feel oppressed by them but fail to see God and the working out of His purposes in the picture at the same time. It presents a situation where disciplined self-control may be absolutely necessary. We must firmly grasp that human nature is just below the surface in us; it always wants to regain its former enslavement of us.
So, being before the civil authority is not merely a civil matter. It presents a situation that is a personal matter between us and the unseen God.