Names of God: Extrabiblical "Trinity"

A few quotes from Benjamin Breckinridge Warfield on God.

[Works of B. B. Warfield Volume IX, Studies in Theology]

“The nature of God has been made known to men, therefore, in three stages, corresponding to the three planes of revelation, and we will naturally come to know Him, first, as the infinite Spirit or the God of nature; then [second], as the Redeemer of sinners, or the God of grace; and lastly [thirdly] as the Father, Son and the Holy Ghost, or the Triune God (pp. 110)”

“The essential elements which enter into and together make up this great revelation of the Triune God are, however, most commonly separately insisted upon. The chief of these are the three constitutive facts:

(1) that there is but one God (Deut. 6:4; Isa. 64:6; 1 Cor. 8:4; Jas. 2:19);

(2) that the Father is God (Matt. 11:25; John 6:27; 8:41; Rom. 15:6; 1 Cor. 8:5; Gal. 1:1, 3, 4; Eph. 4:6; 6:23; 1 Thess. 1:1; Jas. 1:27; 3:9; 1 Pet. 1:2; Jude 1);

the Son is God (John 1:1, 18; 20:28; Acts 20:28; Rom. 9:5; Heb. 1:8; Col. 2:9; Phil. 2:6; 2 Pet. 1:1);

and the Spirit is God (Acts 5:3, 4; 1 Cor. 2:10, 11; Eph. 2:22); and

(3) that the Father, Son, and Holy Ghost are personally distinct from one another, distinguished by personal pronouns, able to send and be sent by one another, to love and honor each the other and the like (John 15:26; 16:13, 14; 27:8, 18, 23; 16:14; 17:1).

The doctrine of the Trinity is but the synthesis of these facts, and, adding nothing to them, simply recognizes in the unity of the Godhead such a Trinity of persons as is involved in the working out of the plan of redemption. In the prosecution of this work there is implicated a certain relative subordination in the modes of operation of the several persons, by which it is the Father that sends the Son and the Son who sends the Spirit; but the three persons are uniformly represented in Scripture as in their essential nature each alike God over all, blessed forever (Rom. 9:5); and we are therefore to conceive the subordination as rather economical, that is relative to the function of each in the work of redemption, than essential, that is, involving a difference in nature. (pp. 113-114)”

[I edited with my emphasis, and for clarity in reading]