If both of the nouns in a predicate nominative construction like this one have the article, or if both lack the article, this is significant as well. In that case, the two nouns become interchangeable. That is, if “Word” had the article, and “God” did, too, this would mean that John is saying that “God was the Word” and the “Word was God.” Both would be the same thing. Or, if neither of them had the article, we would have the same idea: an equating of all of God with all of the Word. “God” and “Word” would be interchangeable and equal terms.
