Note 13 at Eph. 3:10: The particulars of the church were a mystery in the Old Testament. But in the New Testament every detail of this mystery is intended to be fully revealed even to the demonic powers (see note 14 at this verse, below). God's church is like a city set on a hill for all the world to see (Mt. 5:14).

Note 14 at Eph. 3:10: In this same letter, Paul uses this same terminology (principalities and powers) to refer to the demonic realm (Eph. 6:12). Therefore, he is saying here that the church is to instruct the demonic realm about the many features or forms (see note 15 at this verse, below) of God's wisdom. Of course, this is not to benefit them, it is to "rub their nose" in the defeat that Jesus won over them. As we walk in the power and victory that Jesus provided, we constantly show Satan and his demons their folly and God's infinite wisdom.

Note 15 at Eph. 3:10: The dictionary defines "manifold" as "1. of many and diverse kinds; 2. having many features or forms" (American Heritage Dict.). God's wisdom is many faceted and unable to be comprehended by human intellect alone. We need the revelation knowledge (see ref. h at Eph. 3:3, p. 1108) of the Holy Spirit to grasp God's infinite wisdom (Ps. 147:5; Rom. 11:33; v. 8).