Isaiah (Hebrew: יְשַׁעְיָהוּ, Stanard Yəšaʿyáhu Tiberian Yəšaʿăyāhû ; Greek: Ἠσαίας, Ēsaiās ; Arabic: اشعیاء, Ash-ee-yaa ; "Salvation of/is YHWH") is the main figure in the Biblical Book of Isaiah, and is traditionally considered to be its author. He was an 8th-century BC Judean prophet who declared all the world to be under Yahweh's control, and who warned his people that their nation would be destroyed if they turned from Yahweh.