This scholarly treatment of the passage and the language of 1 John 5:1 is long overdue. In light of this article, I don’t see how Calvinists can continue to reference this erroneous argument. You can down load the article from SEA:
Here is the author’s abstract:
A number of scholars have appealed to the Greek tenses of 1 John 5:1 as definitive proof that the verse teaches that regeneration precedes faith. But this argument is untenable. The purposes of the present article are (1) to draw attention to the falsity of the argument and to explain why it is invalid, and (2) to counter the contention that the underlying concern of the grammatical argument (i.e., that 1 John 5:1 implies that regeneration precedes faith) can be rescued by appeal to a pattern in 1 John of indicating the results of regeneration. It is questionable whether the tenses in 1 John 5:1 suggest any chronological or causal relationship between faith and regeneration since some grammarians deny that Greek tenses grammaticalize time, and more importantly, one of the tenses in the passage occurs in a substantival participle, which can be devoid of time significance. If the tenses are temporally related, as seems most probable, then Greek grammar suggests either that believing and being begotten of God are portrayed as contemporaneous, or perhaps more likely, that believing logically precedes being begotten of God. Invocation of statements elsewhere in 1 John indicating the results of regeneration does not rescue 1 John 5:1 as a proof text for regeneration preceding faith because of, inter alia, the distinctive and crucial role of faith in the epistle and Johannine theology.