Question: In Col. 1:15, why does Paul call Jesus 'firstborn'? Did Paul not believe that Jesus was God?
TWH: Great question. The New Testament is pretty clear throughout that Jesus is not a creature. He is preexistent and possesses all of the divine attributes. It's important when we look at this designation of Jesus that we think about the whole expression, not just the lexeme. Paul, in Col. 1:15, calls Jesus the "firstborn of all creation" (πρωτότοκος πάσης κτίσεως). By the way, Paul uses the same word in Col. 1:18: "firstborn from the dead" (πρωτότοκος ἐκ τῶν νεκρῶν). See also what John wrote in Rev. 1:5: "the firstborn from the dead" (ὁ πρωτότοκος τῶν νεκρῶν). By the way, I have found Jerry Sumney's observations about these two last two verses extremely interesting. In his commentary on Colossians (New Testament Library series), he points out how ἀρχή and πρωτότοκος are used in close proximity in both passages, that is Col. 1:18 and Rev. 1:5. It was because of Sumney that I really started considering "ruler" as the likely candidate for how we should understand the use of ἀρχή in Col. 1:18, even though he opts for hearing two sense meanings in the single lexeme. We often translate that word as "beginning," not "ruler." But wouldn't the latter fit exceptionally with what Paul is trying to say, even all the way back in Col. 1:15? –That Jesus is above everything. He is the rightful heir to everything and is above everything and to whom everything belongs. And because of that, he is the one who rules over all that belongs to him. It seems to fit quite nicely if you ask me. Sumney is spot on when he says that use of "firstborn" in Col. 1:15 speaks to his "priority and rank" (Colossians: A Commentary, 73). Couple that with what I've said about Col. 1:18 and that understanding is bolstered even more.
There is nothing really in the text itself or the surrounding context that suggests anything about Jesus being a created being. Such uses of "firstborn" are found. In fact, I would say that that meaning, referring to a physical descendant, is probably the default sense. But default is not absolute. And when the early church is trying to communicate who Jesus is, using language that everyone is familiar with is a necessary step in unveiling more and more about the one who "explains the Father" (John 1:18). People in the first century would have been quite familiar with uses that were beyond the default sense meaning. We can do the same thing today with different words and their default sense meanings. In fact, this is a pretty basic linguistic principle. We think about these matters subconsciously. In other words, when we hear something someone is saying and the intended meaning is something other than the default sense meaning, the data we already have stored up about the topic being discussed automatically steers our attention away from the default sense meaning. Here's my point, when it comes to the use of "firstborn" in Col. 1:15, the Colossians would have not even considered the default sense meaning. In no moment would they have considered that Paul might be saying that Jesus was a created being. The intended sense meaning in Luke 2:7 and Heb. 11:28 would not have entered their thought process. Everything Paul (and the rest of the apostles, for that matter) could have taught about who Jesus is, which we can assume based on our understanding of his collected writings, removed the "created" sense that the term "firstborn" could have carried were the subject anyone or anything else.