Didymus the Blind : The words ek sou can be understood in two ways: either "by you" or "from the time that." The interpretation "by you" gives the following sense: When one who has engaged the preparatory exercises in view of virtue and perfect wisdom [the promise of faith] remains at that preparatory level [that is, the relation with Hagar], in a sense he wrongs virtue, because he has not properly employed what comes before it. But the translation "from the time that" also yields the same sense, the only difference being the one already mentioned, because in this case too virtue is wronged by one who is eager to have children from the preliminary exercises alone and who makes of this level of child bearing a kind of end in itself. — ON Genesis 240