Why is Ἰάκωβος James and not Jacob? (Monday with Mounce 162)

One of my students asked this rather fundamental question last week. Good question, and I hadn’t thought about it before, and I need your help to answer it.

BDAG says that the name Ἰακώβ (יַעֲקֹב) is “the un-Grecized form of the OT, is reserved for formal writing, and esp. for the patriarch. It is also spelled Ἰακούβ.

The Greek lexical form Ἰάκωβος, with an alternate spelling Ἰάκουβος, is the Hellenized form of Ἰακώβ. 

The normal English translation is “Jacob”; “James” does not appear in the OT (of the ESV). “Jacob” occurs in the NT 26x, always of the patriarch except for the two references to Jesus’ paternal grandfather (Matt 1:15f.).

Unfortunately, I do not have access to the resources that answer this question definitively. BDAG says to check the Oxford English Dictionary; if anyone has access to this and can post their discussion, that would be great. I am hesitant to continue without resources, but here is the best I can see.

From what I can tell, the shift from “Jacob” to “James” is more related to changes in spelling through a series of languages:

• Latin: “Iacobus” (or “Jacobus”)
• Late Latin: “Iacomus” (the b and the m sounded similarly)
• My copy of the Vugate has: “Iacob”
• Middle English: Jacomus

One source I read says the French “Gemmes” is what became “James.” My old Websters Dictionary (I still like paper dictionaries) says that “James” is from the French, which in turn was derived from the Late Latin “Jacobus.”

Wikipedia says, “The development Iacobus > Iacomus is likely a result of nasalization of the oand assimilation to the following b (i.e., intermediate *Iacombus) followed by simplification of the cluster mb through loss of the b.” This seems to hold up from other sources I am reading.

By the time you get to the King James, the name “James” was firmly established (for whatever reason), and they used that instead of “Jacob.”

So I hesitate to publish a blog without a clear answer, but I am curious and invite you to help me solve this riddle.

William D. [Bill] Mounce posts about the Greek language, exegesis, and related topics at Koinonia. He is the author of numerous books, including the bestselling Basics of Biblical Greek, and is the general editor for Mounce's Complete Expository Dictionary of the Old and New Testament Words. He served as the New Testament chair of the English Standard Version Bible translation, and is currently on the Committee for Bible Translation for the NIV. Learn more about Bill at BillMounce.com, and visit his other blog on spiritual growth, Life is a Journey, at BiblicalTraining.org.