Louis Berkhof, Summary of Christian Doctrine, Part II : The Doctrine of God and Creation, Chapter VIII : The Divine Decrees.
The decree of God is His eternal plan or purpose, in which He has foreordained all things that come to pass. Since it includes many particulars, we often speak of the divine decrees in the plural, though in reality there is but a single decree. It covers all the works of God in creation and redemption, and also embraces the actions of men, not excluding their sinful deeds. But while it rendered the entrance of sin into the world certain, it does not make God responsible for our sinful deeds. His decree with respect to sin is a permissive decree.
Louis Berkhof, Summary of Christian Doctrine, Part II: The Doctrine of God and Creation, Chapter VIII: The Divine Decrees.