John 1:1 and The Deity of Christ

"Some have claimed that 'the Word was God' merely identifies Jesus as a god rather than identifying Jesus as God, because the Greek word for God, Theos, is not preceded by a definite article. However, in Greek grammar, Colwell's Rule indicatesthat the translation 'a god' is not required, for lack of an article does not necessarilyindicate indefiniteness ('a god') but rather specifies that a given term ('God') is the predicate nominative of a definite subject ('The Word'). This means that the context must determine the meaning of Theos here, and the context indicates that this 'God' that John is talking about ('the Word') is the one true God who created all things . . . "