Referring to the question: Does " theos "without article in greek perhaps mean not god the father but simply "a God".
Is it possible according to grammar?
Dr. Jeff Vickens says it's complicated. Listen to his answer to JW. Begin listening at 14:40 to come to the core.
https://www.youtube.com/watch?v=vH_qV0UcJZs
https://www.youtube.com/attribution?v=i1Lek2-uQvs
Further excerpt from from gotquestions
www.gotquestions.org/New-World-Translation.html
There is a good reason why theos has no definite article in John 1:1 and why the New World Translation rendering is in error. There are three general rules we need to understand to see why.
1. In Greek, word order does not determine word usage like it does in English. In English, a sentence is structured according to word order: Subject - Verb - Object. Thus, "Harry called the dog" is not equivalent to "the dog called Harry." But in Greek, a word's function is determined by the case ending found attached to the word's root. There are two case endings for the root theo: one is -s (theos), the other is -n (theon). The -s ending normally identifies a noun as being the subject of a sentence, while the -n ending normally identifies a noun as the direct object.
2. When a noun functions as a predicate nominative (in English, a noun that follows a being verb such as "is"), its case ending must match the noun's case that it renames, so that the reader will know which noun it is defining. Therefore, theo must take the -s ending because it is renaming logos. Therefore, John 1:1 transliterates to "kai theos en ho logos." Is theos the subject, or is logos? Both have the -s ending. The answer is found in the next rule.
3. In cases where two nouns appear, and both take the same case ending, the author will often add the definite article to the word that is the subject in order to avoid confusion. John put the definite article on logos (“the Word”) instead of on theos. So, logos is the subject, and theos is the predicate nominative. In English, this results in John 1:1 being read as "and the Word was God" (instead of "and God was the word").
The most revealing evidence of the Watchtower's bias is their inconsistent translation technique. Throughout the Gospel of John, the Greek word theon occurs without a definite article. The New World Translation renders none of these as “a god.” Even more inconsistent, in John 1:18, the NWT translates the same term as both "God" and "god" in the very same sentence.
The Watchtower, therefore, has no hard textual grounds for their translation—only their own theological bias. While New World Translation defenders might succeed in showing that John 1:1 can be translated as they have done, they cannot show that it is the proper translation. Nor can they explain the fact that that the NWT does not translate the same Greek phrases elsewhere in the Gospel of John the same way. It is only the pre-conceived heretical rejection of the deity of Christ that forces the Watchtower Society to inconsistently translate the Greek text, thus allowing their error to gain some semblance of legitimacy in the minds of those ignorant of the facts.