From a Greek scholar in response to Paidion:
That’s incorrect. In the Greek it reads “and God was the word” this organization of the wording is for emphasis. It implies that everything God is, the word is. The word contains the definite article because it is the subject. While he’s right that it carries with it the nature of essence, that is because it’s separating the person if the Word (i.e. Christ) from the person of God. If both contained the definite article we would be left with sabellianism.
Essentially what John is saying is that Jesus possesses all the attributes of the Father, but the lack of the definite article demonstrates that he is not the Father.