'Ruler' in the Bible

Let every individual be obedient to those who rule over him; for no one is a ruler except by God's permission, and our present rulers have had their rank and power assigned to them by Him.

Therefore the man who rebels against his ruler is resisting God's will; and those who thus resist will bring punishment upon themselves.

For judges and magistrates are to be feared not by right-doers but by wrong-doers. You desire--do you not? --to have no reason to fear your ruler. Well, do the thing that is right, and then he will commend you.

And again Isaiah says, There will be the root of Jesse, and he who comes to be the ruler over the Gentiles; in him will the Gentiles put their hope.