Question: Dr. Luginbill, I would like to open this letter by stating that this is one of the finest Christian websites I have ever seen. It is absolutely chock full of information. My question is in reference to the Trinity. I have read various articles which state that the concept of the Trinity is not scriptural and that no evidence of it can be found in the Bible. Among the sects that hold this position are the Christadelphians, not to mention other religions such as Islam which cite this as evidence that Christianity is based on ancient pagan beliefs strongly influenced by Greek culture. If you could shed some light on this it would be much appreciated.
Response: Thank you so much for you encouraging words. It so happens that there is information on the website about the Trinity and about the questioning of the Trinity. I don't want to be too repetitive here (see the links below). Just let me say that this is a common slander on the Bible that one hears all the time, especially in academia. The Trinity is in the first chapter of Genesis (cf. "let us make man in our image) and is ubiquitous in the Old Testament not to mention the New Testament; for example our Lord's command to the disciples to go and make disciples of all nations by first "[Spirit] baptizing them into the Person of the Father and of the Son and of the Holy Spirit" (Matt.28:19). It is true that many things which are actually in the OT were not fully understood even by those whom God used to write it, for example the calling out the gentiles to fill up the Body of Christ:
The prophets [of old] diligently investigated and inquired about this salvation [destined to come to you gentiles (cf. v.1)], when they prophesied about the grace [that was to come] to you (i.e., the mass calling out of the gentiles). For they were eager to discover the precise time the Spirit of Christ within them was signifying as He predicted the sufferings of Christ and the glories that would follow (i.e., the filling up of the Church). For it was revealed to them that in prophesying these things, they were not so much serving themselves as they were you - and these same things have now been proclaimed to you through those who gave you the gospel through the Holy Spirit, sent from heaven - even angels want to look into these things.
1st Peter 1:10-12
What is true of the filling up of the Church is also true of the Trinity, that is, it is certainly present in the Old Testament but not necessarily so clear that anyone at the time could have understood it explicitly without the revelation now available through the Spirit. As things stand now, however, we can see it clearly enough, even in the OT. For how else are we to understand, for example, Isaiah 48:16b - "and now the Lord God (i.e., the Father) has sent Me (i.e., the pre-incarnate Christ) and His Spirit (i.e., the Holy Spirit)" - ? Or take Isaiah 63:11-12 where "He" (the Father), the Holy Spirit, and "His glorious Arm of power" (= Jesus Christ; cf. Is.53:1 "to whom has the Arm of the Lord been revealed?") are all right there in the same context as clearly separate Persons.
After all, even the disciples didn't understand the principle of the resurrection of the Messiah until after He rose (Jn.20:9), but that surely doesn't mean that His resurrection was not prophesied (for we have that from Jesus Himself: e.g., Matt.17:22-23). After the coming of the Spirit, their understanding is quickened (cf. Jn.16:13). It would be a sad thing for any believer to give into worldly speculation about what the Bible doesn't say instead of seeking God through His scriptures under the guidance of the Spirit. Today we have the full revelation of God in the complete Bible, and the illuminating ministry of the Spirit is available to us all. There are no answers worth knowing that are not contained within the Bible's pages. So if you and I as believers have no problem finding the Trinity therein, the fact that unbelievers of various stripes refuse to see it should be no more surprising than their other blind spots (like refusing to accept the divinity of Jesus Christ, for example). For a complete run down on the biblical support for the doctrine of the Trinity, please see in Bible Basics part 1: Theology, section II: "The Persons of God: The Trinity". There is also good introductory information in the following e-mail responses:
Questioning the Trinity
The Trinity in Isaiah 63
The One True God and the Trinity in the Old Testament
Explaining and Defending the Trinity and the Person of Christ.
Yours in the One true God, Father, Son, and Holy Spirit,