A form of Isaiah via Greek and Latin tradition, meaning Yahweh is salvation.
Esaias is the Greek and Latin transliteration of the Hebrew name Yeshayahu — rendered in English as Isaiah — and carries the luminous meaning 'God is salvation' or 'the LORD saves.' This form of the name entered European usage through the Septuagint, the Greek translation of the Hebrew scriptures produced in Alexandria around the third and second centuries BCE, and from there passed into Latin biblical tradition.
In the Vulgate Bible and in early Protestant translations such as Luther's German Bible, 'Esaias' was the preferred rendering, which is why the name appears under this spelling in the King James Bible of 1611 and in Reformation-era Lutheran records across Germany, Scandinavia, and the Netherlands. The prophet Isaiah — Esaias to the early Church — is one of the towering figures of the Hebrew Bible, author of a book of extraordinary poetic prophecy that Christians read as anticipating the life of Jesus, including the famous passages about a 'suffering servant' and the birth of Immanuel. This theological weight made Esaias a revered choice for Christian families during the Reformation period, when parents frequently chose names directly from scripture.
Johann Sebastian Bach was baptized in the Lutheran tradition and would have been familiar with the name from biblical readings. The form Esaias gradually gave way to Isaiah in English usage from the eighteenth century onward, but Esaias has experienced a quiet revival among parents drawn to its antique solemnity and its connection to the deep Christian and Hebraic heritage — a classical name that sounds simultaneously ancient and quietly distinctive.