Berkhof on the decrees

Reformed theology stresses the sovereignty of God in virtue of which He has sovereignly determined from all eternity whatsoever will come to pass, and works His sovereign will in His entire creation, both natural and spiritual, according to His pre-determined plan. It is in full agreement with Paul when he says that God "worketh all things after the counsel of His will," Eph. 1:11. For that reason it is but natural that, in passing from the discussion of the Being of God to that of the works of God, it should begin with a study of the divine decrees.

Though we often speak of the decrees of God in the plural, yet in its own nature the divine decrees is but a single act of God. This is already suggested by the fact that the Bible speaks of it as a prothesis, a purpose or counsel. It follows also from the very nature of God. His knowledge is all immediate and simultaneous rather than successive like ours, and His comprehension of it is always complete. And the decree that is founded on it is also a single, all-comprehensive, and simultaneous act. As an eternal and immutable decree it could not be otherwise. There is, therefore, no series of decrees in God, but simply one comprehensive plan, embracing all that comes to pass. Our finite comprehension, however, constrains us to make distinctions, and this accounts for the fact that we often speak of the decrees of God in the plural.

The word "counsel," which is one of the terms by which the decree is designated, suggests careful deliberation and consultation. It may contain a suggestion of an intercommunion between the three persons of the Godhead. . . . There may be a great deal in the decree that passes human understanding and is inexplicable to the finite mind, but it contains nothing that is irrational or arbitrary. God formed his determination with wise insight and knowledge. [cf. Eph. 3:10-11, Ps. 104:24, Prov. 3:19, Jer. 10:12, Jer. 51:15, Ps. 33:11, Prov. 19:21]

Quotes from Louis Berkhof, Systematic Theology (pp. 100, 102 & 103-4)