The Book of the Prophet Isaiah is the first book of the four major prophets. Isaiah lived in Judah during the reign of Hezekiah. Eerdman's Handbook states, "There is nothing to equal his tremendous vision of God and the glory in store for God's people until we reach John's Book of Revelation, at the end of the New Testament."
The Book of the Prophet Jeremiah is the second book of the four major prophets. Jeremiah lived during the fall of Judah to the Babylonians. To no avail, he warned of the coming disaster and the need to return to God.