The doctrine of the Trinity is very clearly taught in the scriptures. But is it? Some anti-Trinitarians argue that the doctrine of the Trinity cannot come from the Bible because the word "Trinity" does not appear in the Bible.
But would it actually need to? If you haven't already, look at the header image. In it, I have described an animal. I did not use the animal's name. What animal do you think it is? Now that you have read the meme, it should be obvious that I was talking about a Siberian tiger. I never once said the word "tiger", but you knew I was talking about one. You see, then, that the word does not need to be present for the concept to be clearly seen.
In fact, the word does not need to exist at all. In the scientific community, the Siberian tiger is known as "Panthera tigris altaica". Panthera tigris altaica and Siberian tiger both mean the same thing. We don't even really need a name for it. Remember, before the tiger got its name, the tiger already existed, and my description of it would still have worked. Similarly, the word "Trinity" is just a name that applies to a concept that already existed, and was clearly taught in the scriptures. We don't even need to call it the Trinity. We could call it the Trilogy, or the Thirdigy, or even something daft like the FaSoHo. They would all work. Someone who doesn't know the word "Trinity" could still come to the conclusion that the Father, Son and Holy Spirit are all one God, just by reading the scriptures. In fact, we could even eliminate this problem altogether by simply changing the word "Trinity" for an interchangeable term: The Godhead (Colossians 2:9).
Furthermore, just as the word "Trinity" does not appear in the Bible in a positive sense, it also isn't in the Bible in a negative sense. Sure, the Bible doesn't say "God is a Trinity", but it also doesn't say "God is not a Trinity". And yet, anti-Trinitarians don't just stop at pointing out that the word Trinity isn't in the Bible. They go even further and try to show that the Bible doesn't teach the Trinity. In other words, the argument is hypocritical. They obviously know the Bible doesn't have to use exact words to describe a concept, because they try to prove a concept using inexact words in the Bible.
To really turn this argument on its head, let's look at a verse anti-Trinitarians use to "prove" Jesus is not God, and therefore God cannot be a Trinity consisting of the Father, Son and Holy Spirit. In Matthew 19:16-22, Mark 10:17-22 and Luke 18:18-23, we find a story about a man coming to Jesus and asking Him how to get to Heaven. He specifically calls Jesus "Good Teacher", to which Jesus replies "Why do you call Me good? No one is good but One, that is, God." Anti-Trinitarians argue that this means Jesus cannot be God.
Now, note first, Jesus does not say "there is no Trinity" or "I am not God". It's not in this story, nor can it be found in the entire Bible. All Jesus does is ask "Why do you call Me good? No one is good but One, that is, God." Therefore, they are relying not on exact words, but on what they perceive to be the description of a concept. This creates a double standard. When it comes to proving the Trinity, they expect us to find "God is a Trinity" in those exact words. When it comes to allegedly disproving the Trinity, they get a free pass on the exact words thing. Either the anti-Trinitarian did not think their argument through, or they are being deliberately dishonest.
In order to be more honest, we are going to allow the anti-Trinitarian to use the concept that God is not a Trinity in this verse. However, by the same token, we can look for the concept of the Trinity in this verse. Here's the problem: Jesus isn't saying "I'm not good, because only God is good, and I'm not Him". Rather, the entire Gospel depends on the goodness of Christ! If Jesus Christ is not good, then crucifying Him could not save sinners. Therefore, we can construct the following syllogism:
Premise 1: only God is good.
Premise 2: Jesus is good.
Conclusion: Jesus is God.
This, of course, does not prove the Trinity. The Holy Spirit is nowhere found in this passage, and so proving the Trinity actually requires using more of the Bible. Rather than go into too much detail, I will simply link to my previous article on this topic.
In the link above, I use the scriptures to defend the argument that, since there is one God, yet there are three separate beings described as God, these three beings must be the one Triune God, i.e. are a Trinity.
So you see, the word "Trinity" does not have to appear in the Bible in order for the Trinity to be described in the Bible. The concept of the Trinity is, indeed, clearly seen in the scriptures. The word "Trinity" is just the common name, and any other name would suffice. Furthermore, anti-Trinitarians acknowledge that the word does not have to appear every time they try to use the Bible to refute the Trinity. In order to remain consistent, they must acknowledge that the word does not have to appear for the concept to be discussed, but when they do, that backfires, because the Bible does clearly show the Trinity, even in the verses anti-Trinitarians use to try to disprove it.