I don't know who the "him" is and what "moral hook" this person shouldn't be released from, but one has to stop reading Jewish Scripture like a Christian and think that every time the Tanakh says something that it is at the same time saying the action was moral. The actions are not justified even though they come from inspired Scripture, at least in the way Jews read their Scriptures.
These are very ancient stories, attributing customs to a paradigm where mythology was the device to attribute all things to Providence. This makes it a static snapshot of an ancient era long gone, and therefore not a means of justifying customs. Jews now use science and critical analysis to explain our history, not the texts of the religion of my people.
However, Judaism does not see a difference between direct revelation as written in Scripture and the more historical explanation. Since the God concept of Judaism may be just as much of an ancient literal device as the mythology, the end is still the same. This is our particular custom and it is as much value as those customs cherished and practiced by non-Jews (some of which are equally as odd to us), regardless of the origin. Scripture is about who Jews are, the good and the bad of my people.