Abraham b. Ezra's 'spirantized peh in the Arabic language': The rules of grammar versus the requirements of exegesis and polemic

Abraham b. Ezra's use of the phrase 'spirantized peh [peh rafah] in the Arabic language' paralleling the function of the Biblical Hebrew vav with that of the Arabic fa has long been viewed as perplexing: often the proposed syntactic function does not accord with the usage of the classical Arabic conjunction fa. Ibn Ezra had Judeo-Arabic usage in mind, where fa' takes on numerous functions beyond the strict boundaries of classical Arabic - And his keen discovery has only recently been independently 'rediscovered' in modern scholarship. In instances where Judeo-Arabic usage cannot provide a basis for Ibn Ezra's assertion, we argue that the exegete's polemical motives regarding specific instances of the biblical vav led him to expand the use of the Arabic particle even beyond what was permissible in Judeo-Arabic, making manipulative use of his own superiority in Arabic and his readers', Jews in Christian Europe, ignorance of it.