Smear the gall of the fish on his eyes: See 6.9.

The medicine will make the white films shrink and peel off from his eyes may be rendered “the medicine will make the white film-like stuff that is covering his eyes shrink and peel off.” New Revised Standard Version is following the Greek in saying that the white films … [will] peel off. Good News Translation says “you can peel it off.” In verse 13 Tobias does peel the films from his father’s eyes, so that it is permissible to bring that detail forward to this point; but it is not necessary. Translators should follow New Revised Standard Version unless they feel strongly otherwise.

Your father will regain his sight and see the light: What Tobit sees will be Tobias himself (see verse 14); but translators should not actually say that here in this verse. If at all possible, the model of New Revised Standard Version should be followed. Another way to say it is, “Then your father’s eyes will be healed and he will see the light,” or in languages that do not have the passive voice, “Then God will heal your father’s eyes and he will see the light.”

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on Tobit. (UBS Helps for Translators). New York: UBS, 2001. For this and other handbooks for translators see here.