Hayes, in her article on impurity in Ancient Jewish society, states that it is commonly misconceived that the expulsion of the Gentile wives was a result of Judaean exceptionalism and nationalism. Hayes points out that the theory is not correct arguing that the root cause is largely a fundamental and core belief found within the religious laws of the Judaeans. Ezra, Hayes explains, imagined Israel as divinely ordained to remain pure and holy, set apart and without the influence of other nations in Canaan, just as the Priestly division were commanded, by God, to practice marriage exclusivity. In reaction to contemporaries, such as Hayes and Klawans, who argue that Ezra–Nehemiah's purity ideology is a product of conservative "ritual" and "moral" purity, independently; Olyan claims that Ezra–Nehemiah's alien expulsion mandate was a result of a melding ideology taken from the two seemingly independent ideas of, "moral" and "ritual" purity and remains exclusive to the particular narrative of Ezra–Nehemiah. Moral purity has familial implications, which the lack of may cause disruption in the cohesiveness of the family unit. Transgressing Israelite moral structure was feared to cause violations of the commandments, which ordained by God, must be followed to maintain ethnical identity. The influence of gentile women and culture upon Israelite men and posterity, through the eyes of ancient Judaean Priests, could turn Yahweh worshippers towards foreign deities and hedonism. Ritual purity stresses the importance of keeping to sacred practices dictated by revered predecessors and the Holy Scriptures. Olyan believes that Ezra's expulsion of the gentiles could also be linked with the idea that outside lineage would initially pollute the priestly bloodline, acting as an apparatus to destroy "right" ritual practice.