How did the name Jacob become James in the New Testament?

Answer

In the original Greek of the New Testament, the names Jacob and James are variations of the same root—both names derive from the Hebrew name Yaaqob (יַעֲקֹב), which is rendered as “Jacob” throughout the Old Testament (e.g., Genesis 25:29).

In the Greek language, the Hebrew name Yaaqob is transformed into Iakób (Ἰακώβ) in a direct translation. This term is consistently translated as “Jacob” in the New Testament. For instance, when Matthew mentions the son of Isaac and the father of Joseph, the husband of Mary, he uses Iakób. Both of these men were called Jacob; see Matthew 1:2 and 8:11.

During Jesus’ time, Jacob was a commonly used name, and many individuals named their sons after the patriarch. However, due to the strong influence of Greek language and culture in the society, the name also took on a Greek form, resulting in Iakóbos (Ἰάκωβος). In English translations, this is rendered as “James.”

The transition from Iakób to Iakóbos exemplifies a process of Hellenization or Graecization—adapting a word to Greek structure and spelling. A similar phenomenon occurs in English, where names of foreign origin are often Anglicized for English speakers. For example, the Scottish name Cailean can be Anglicized to Colin, and the Welsh name Eoghan becomes Owen. Eoghan and Owen are variations of the same name, with only differences in spelling and pronunciation. The same applies to Iakób and Iakóbos.

The question remains as to why Iakóbos is translated as “James” rather than “Jacob.” This involves an intriguing etymology, tracing the Greek word Iakóbos through its evolution from Greek to English. Prior to Jerome and the Latin Vulgate, the Greek Septuagint had been translated into Latin, where Iakóbos was transliterated as Iacobus (or Jacobus)—still closely resembling Jacob. However, in Late Latin, a slight alteration in spelling and pronunciation occurred.

The name started to be written as Iacomus (or Jacomus). Early French adapted the Latin name and truncated it to Gemmes (or Jammes), and from there English took it as James.

In the English New Testament, the name Jacob is mostly reserved for references to the Old Testament patriarch (24 out of 26 times). James is used of any of several men named James, including two of Jesus’ disciples and the half-brother of Jesus.