John Wesley on Ephesians 6:10

Brethren - This is the only place in this epistle where he uses this compellation. Soldiers frequently use it to each other in the field. Be strong - Nothing less will suffice for such a fight: to be weak, and remain so, is the way to perish. In the power of his might - A very uncommon expression, plainly denoting what great assistance we need as if his might would not do, it must be the powerful exertion of his might.