 The argument comes when Nehemiah notices that the Judeans were marrying people outside of their lands (exogamy) whose children spoke the same language.Although this came during the 52 days of the construction of the wall, we are not sure how he noticed the issue.The non clarity in the text according to Wright is as if Ezra already outlawed Judean men not to marry any one outside of their land, then why is Nehemiah noticing it thirteen years later.