John Wesley on Ephesians 6:11

Put on the whole armour of God - The Greek word means a complete suit of armour. Believers are said to put on the girdle, breastplate, shoes; to take the shield of faith, and sword of the Spirit. The whole armour - As if the armour would scarce do, it must be the whole armour. This is repeated, ver.13, because of the strength and subtilty of our adversaries, and because of an "evil day" of sore trial being at hand.