Yeshaya (ben Amotz) is a book of Sefer Neviim prophesying about both Punishment and future Redemption during the reigns of Kings Uzia, Yosam, Achaz and Chizkiyahu.
The Book of Isaiah, also known as the Book or Sefer of Yesha'ayhu (alternatively spelled Yeshayahu, Yesha'ayah or Yeshayah; Heb. ספר ישעיה or ספר ישעיהו), is a book in the Prophets or Neviim section of the Tanach that collects the prophecies and stories about the life of the prophet Isaiah or Yesha'ayahu, who prophesied during the reigns of the Judian kings Uzziah, Yotam, Achaz and Chizkiyahu (circa the 8th and early 7th centuries BCE per secular dating, or circa the 7th and 6th centuries BCE per the traditional Jewish dating).
The Talmud (Bava Batra 14b) defines the contents of the book as being entirely about consolation, because most of the prophecies are redemption prophecies.
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