Kent Jackson explains the role prophetic foresight plays in the authorship of Isaiah.
Kent Jackson, "Authorship of the Book of Isaiah," Studies in Scripture: Volume Four: 1 Kings to Malachi (Deseret Book Company: Salt Lake City, 1993) 80-85
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The fundamental issue in the multiple-authorship theory is whether or not a prophet can see beyond his own time. Those who begin with the supposition that men cannot see beyond their own day must logicaly conclude that Isaiah could not have written those sections of the book that speak to a different historical setting form his own. But those who understand the true nature of revelation and prophetic foresight have no trouble with prophecies of future events. Latter-day Saints are blessed with abundant evidence revealed in the latter days that shows that God can indeed inspire his servants with views of future days and, when appropriate, they impart vision to others.
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