From Mark Shea:*And the Angel Raphael appears under a false name to Tobit. How can Catholics explain that such "divinely inspired" books would endorse lying and get their facts wrong? The same way we deal with other incidents in Scripture where similar incidents of lying or "errors" happen.
Let's take the problem of alleged "factual errors" first. The Church teaches that to have an authentic understanding of Scripture we must have in mind what the author was actually trying to assert, the way he was trying to assert it, and what is incidental to that assertion.
For example, when Jesus begins the parable of the Prodigal Son saying, "There was once a man with two sons," He is not shown to be a bad historian when it is proven that the man with two sons He describes didn't actually exist. So too, when the prophet Nathan tells King David the story of the "rich man" who stole a "poor man's" ewe lamb and slaughtered it, Nathan is not a liar if he cannot produce the carcass or identify the two men in his story. In strict fact, there was no ewe lamb, no theft, and no rich and poor men. These details were used in a metaphor to rebuke King David for his adultery with Bathsheba. We know what Nathan was trying to say and the way he was trying to say it. Likewise, when the Gospels say the women came to the tomb at sunrise, there is no scientific error here. This is not the assertion of the Ptolemiac theory that the sun revolves around the earth. These and other examples which could be given are not "errors" because they're not truth claims about astronomy or historical events.
Similarly, both Judith and Tobit have a number of historical and geographical errors, not because they're presenting bad history and erroneous geography, but because they're first-rate pious stories that don't pretend to be remotely interested with teaching history or geography, any more than the Resurrection narratives in the Gospels are interested in astronomy. Indeed, the author of Tobit goes out of his way to make clear that his hero is fictional. He makes Tobit the uncle of Ahiqar, a figure in ancient Semitic folklore like "Jack the Giant Killer" or "Aladdin." Just as one wouldn't wave a medieval history textbook around and complain about a tale that begins "once upon a time when King Arthur ruled the land," so Catholics are not reading Tobit and Judith to get a history lesson.
Very well then, but what of the moral and theological "errors"? Judith lies. Raphael gives a false name. So they do. In the case of Judith lying to King Holofernes in order to save her people, we must recall that she was acting in light of Jewish understanding as it had developed until that time. This meant that she saw her deception as acceptable, even laudable, because she was eliminating a deadly foe of her people. By deceiving Holofernes as to her intentions and by asking the Lord to bless this tactic, she was not doing something alien to Jewish Scripture or Old Testament morality. Another biblical example of this type of lying is when the Hebrew midwives lied to Pharaoh about the birth of Moses. They lied and were justified in lying because Pharaoh did not have a right to the truth—if they told the truth, he would have killed Moses. If the book of Judith is to be excluded from the canon on this basis, so must Exodus.
With respect to Raphael, it's much more dubious that the author intended, or that his audience understood him to mean, "Angels lie. So should you." On the contrary, Tobit is a classic example of an "entertaining angels unaware" story (cf. Heb. 13:2). We know who Raphael is all along. When Tobit cried out to God for help, God immediately answered him by sending Raphael. But, as is often the case, God's deliverance was not noticed at first. Raphael introduced himself as "Azariah," which means "Yahweh helps," and then rattles off a string of supposed mutual relations, all with names meaning things like "Yahweh is merciful," "Yahweh gives," and "Yahweh hears." By this device, the author is saying (with a nudge and a wink), "Psst, audience. Get it?" And we, of course, do get it, particularly if we're reading the story in the original Hebrew. Indeed, by using the name "Yahweh helps," Raphael isn't so much "lying" about his real name as he is revealing the deepest truth about who God is and why God sent him to Tobit. It's that truth and not any fluff about history or geography or the fun using an alias that the author of Tobit aims to tell.