Btukfyl

I am translating a religious book from language A to language B and have hired a student worker to help me. He is a native speaker of language A but does not speak language B at all. What I ask him to do is, whenever a Bible verse (for example, Mark 16:16) is mentioned in the book, he will find the corresponding name of the book in language B from a table and then copy and paste the name in language B to my file. Since the book quotes heavily from the Bible, my student has done a lot of work in this translation work.

My question is, should I add my student worker as a cotranslator based on what he did, though he does not know language B at all?

Your student worker sounds like a valuable assistant. But he is not a translator.

Even if he were doing actual translation work, a co-translator indicates someone doing work at the same level that you are, or close. And he's not.

If you want to acknowledge his contribution to your manuscript, by all means give him credit within the book. This can be immediately after your name:

Translated by Zuriel, with assistance from Student Worker.

Or he could be featured prominently in the acknowledgments. Or something in-between, like on the title page but not in the same line as your credit.

Your publisher may or may not want a say in this. But ultimately, what credit you give this worker is between you and him. Honor him if you wish (and if you call him a co-translator, no one is going to question you, if that's the title you really want to use) but don't feel compelled to give him more credit than he's earned.

It sounds like he's done a lot of work and certainly deserves some sort of acknowledgement.

If you want to describe his contribution in one word, like if you are filling out some form where you have to give each person's contribution and they only give space for a word or two, "translator" is about as good a word as I can think of. If you want to mention him in your acknowledgements -- which seems to me like an appropriate thing to do -- you could use a few more words, ranging from "with assistance from Joe Smith" (obviously whatever is actual name is) to, I suppose, a full explanation of what he did.

If you list him somewhere as a co-translator and someone later questions how he could "translate" when he doesn't know language B, so you explain. I suppose if he went around telling people "I translated a book from language A to language B", there could be a problem, but, etc.