With great impudence, the rebellious dare to engage the Lord as if they were equal to such a fight. God hides his great strength and the presumptuous misinterpret this as weakness and become overconfident in their rebellion, thinking that they are a match for the Almighty.
Does this mean that men are really so foolhardy as to launch an attack directly upon God? No, but that is what they do in effect. Calvin says, ‘It is true that mortal man will be ashamed to think of making war against God … yet for all that they do not cease to do it. We do not need to sound a trumpet to God in order to defy him when we intend to make war against him; for if we trouble our neighbour or if we use deceit and extortion, then God sets himself against us. If we really though we made war against him and not against our fellow mortal creatures, would we be so mad as to overreach ourselves as we do?’ (Calvin – English updated).
Barnes questions the translation of the King James Version here which implies that it is the neck of God and the thick or embossed shield of God that is in view. He says that the translation gives this impression by rendering the preposition as ‘on’ or ‘upon’ which should be translated ‘with’. It is the neck and the shield of the rebellious that is spoken of, as he rushes upon the Lord.