The acts of God are divided into two kinds, internal (opera ad intra), and external (opera ad extra), the latter being either immediate (performed without instrumental causes) or mediate (performed through intermediate causes).
The internal acts, or operations, of God are again of two kinds, personal and essential. The personal internal acts of God terminate within the Godhead and pertain to the divine Persons by whom they are performed as peculiar to such Persons (generation and spiration). The essential internal acts of God also terminate within the Godhead, but in them the three Persons of the Trinity concur. These essential internal operations of God are called the eternal decrees of God. Of these there are three : a) the decree of creation, b) the decree of redemption, and c) the decree of predestination.
a. The decree of creation is that essential internal act of the Triune God "by which He purposed to create in the beginning of time heaven and earth and all creatures, for the manifestation of His wisdom, goodness, and power" (A. L. Graebner). The decree of creation is taught in Job 28, 26. 27; Acts 15, 18; Gen. 1, 26; Acts 17, 26; Ps. 136, 5-9.
b. The decree of redemption is that essential internal act of the Triune God by which He most graciously and wisely purposed to redeem fallen and lost mankind through the vicarious atonement of the incarnate Son of God, Jesus Christ, and thus to prepare a way of salvation for the whole world, whose fall He bad foreseen, but not decreed. The decree of redemption is taught in Acts 2, 23: "Delivered by the determinate counsel and foreknowledge of God"; Acts 4, 28 : "To do whatsoever Thy counsel determined before to be done"; Eph. 1, 7-10: "In whom we have redemption through His blood, ... according to the riches of His grace; wherein He bath abounded toward us in all wisdom and prudence ... according to His good pleasure which He hath purposed in Himself"; 1 Pet. 1, 20: ''Who the incarnate Son of God, our Redeemer verily was foreordained before the foundation of the world"; Gal. 4, 4. 5 : "When the fulness of time was come, God sent forth His Son, made of a woman, made under the Law, to redeem them that were under the Law"; John 3, 16: "God so loved the world that He gave His only-begotten Son," etc.
c. The decree of predestination is that essential internal act of the Triune God by which He from eternity, moved only by His grace and the redemption of Jesus Christ, purposed to sanctify and save by faith, through the means of grace, all saints who finally enter into life eternal. The decree of predestination is taught in Eph. 1, 4: "He has chosen us in Him Christ before the foundation of the world"; 2 Thess. 2, 13: "God hath from the beginning chosen you to salvation"; Eph. 3, 11: "According to the eternal purpose which He purposed in Christ Jesus, our Lord"; 2 Tim. 1, 9: "Who hath saved us ... according to His own purpose and grace, which was given us in Christ J esua before the world began"; Rom. 11, 5 : "There is a remnant according to the election of grace"; Acts 13, 48: "As many as were ordained to eternal life believed"; Rom. 8, 29. 30 : "Whom He did foreknow He also did predestinate to be conformed to the image of His Son. . . . Whom He did predestinate, them He also called; and whom He called, them He also justified; and whom He justified, them He also glorified"; 1 Pet. 1, 2: "Elect according to the foreknowledge of God the Father, through sanctification of the Spirit, unto obedience and sprinkling of the blood of Jesus Christ"; Matt. 22, 14: "Many are called, but few are chosen"; Mark 13, 20. 22 : "For the elect's sake, whom He hath chosen, He hath shortened the days . . . to seduce, if it were possible, even the elect."
The doctrine of election will be treated at greater length under its proper bead. Here we refer to it only inasmuch as it belongs to the eternal decrees of God. But in passing, we may say that from the eternal decree of predestination there must be excluded every form of synergism (denial of the sola gratia) and every form of Calvinism (denial of the gratia universalis). For this reason we affirm a) God did not choose the elect in view of their faith (intuitu fidei), and b) God did not predestinate any one to damnation, but earnestly desires all men to be saved (vocatio seria). The apparent discrepancy between particular election (electio particularis) and universal grace (gratia universal is) we acknowledge as a mystery, which is indeed beyond reason, but which we should neither criticize nor try to explain. All attempts to harmonize the two doctrines have resulted either in synergism (the elect were chosen in view of their better conduct, which is opposed to Rom. 3, 22. 23) or in Calvinism (God does not desire to save all, which is opposed to John 3, 16; 2 Cor. 5, 19. 20; 2 Pet. 3, 9; Acts 17, 30; 1 Tim. 4, 2). The Formula of Concord rightly says: "However, since God has reserved this mystery for His wisdom and has revealed nothing to us concerning it in His Word, much less commanded us to investigate it with our thoughts, but has earnestly discouraged us therefrom, Rom. 11, 33 ff., we should not reason in our thoughts, draw conclusions, nor inquire curiously into these matters, but should adhere to His revealed Word, to which He points us." Thor. Decl., XI, 55.
Dr. A. L. Graebner summarizes the decree of predestination as follows : "The decree of predestination is an eternal act of God (Eph. 1, 4; 3, 11; 2 Tim. 1, 9; 2 Thess. 2, 13), who for His goodness' sake (2 Tim. 1, 9; Rom. 9, 11; 11, 5) and because of the merit of the foreordained Redeemer of all mankind (Eph. 1, 4; 3, 11) purposed to lead into everlasting life (Acts 13, 48; 2 Tim. 2,10; Rom. 8, 28. 29), by the way and means of salvation designated for all mankind (Eph. 1, 4. 5; 1 Pet. 1, 2), a certain number (Acts 13,48; Matt. 20, 16; 22, 14) of certain persons (2 Tim. 2, 19; John 13, 18) and to procure, work, and promote what would pertain to their final salvation (Rom. 8, 30; Eph. 1, 11; 3, 10. 11; Mark 13, 20. 22) ." (Outlines of Doctrinal Theology, § 51.)