Is the Trinity biblical? Yes, and no. The technical terms used to explain the doctrine exceed what is taught in the Bible, but there are extensive biblical reasons for accepting the doctrine. Here's a list: 1/

1) There are a fairly limited number of verses where the Son is called God (John 1:1, 1:18, 20:28, Rom. 9:5, Titus 2:13, Heb. 1:8-9) or where the Spirit is called God (Acts 5:3-4). Most of these are contested, and surprisingly they aren't the most important wrt the Trinity 2/

2) The NT continues to affirm a single God (typically associated with the Father), but incorporates the Son into that single identity. This is particularly noteworthy in 1 Cor. 8:6, which seems to incorporate the Son into the Shema and a stoic account of deity. 3/

3) The pre-existence of the Son, most clearly attested in John and Hebrews but evidenced in the synoptic "I have come" sayings, suggests that the Son and Father have been eternally differentiated. 4/

4) Prosopological exegesis (a method that reads OT passages as heavenly discussions) reinforces the differentiation, but adds the Spirit into the mix, suggesting a threefold eternal distinction. 5/

5) The Son and Spirit are shown to be more than angelic cohorts because they are incorporated into cultic worship in the NT in baptism (Matt. 28:18), benediction (2 Cor. 13:14), etc. Canonically, only divine figures are included in such worship. 6/

6) Father, Son, and Spirit are equal not only in the worship we render to them, but in the salvific work they undertake toward us. Indeed, the works of the persons are often identified, especially between Father and Son in John 5:17, 19. 7/

7) OT passages attributed to the Father are attributed to the Spirit or Son in the NT as well, with a similar result.

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8) This shared work is evident in the many triplex statements in the New Testament, where Father, Son, and Spirit are coordinated with one another (i.e., 1 Cor. 12:4-6). Often, one's identify is expressed in relation to another, such as "Spirit of the Son," or "Son of God." 9/

9) Such verses suggest a shared divinity and identity, yet relational distinction. Traditionally, the doctrine of the Trinity includes spiration and generation as the basis for such differentiation... 10/

... spiration/generation can be taken as a logical conclusion read from the sending of the Son and Spirit back into the Godhead to explain the eternal relations. Consubstantiality can be taken as reading the shared actions and titles back into the Godhead. 11/

Taken together, such tropes lead by good and necessary inference to the doctrine of the Trinity.

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