I like Ellen's comment "I'm going to accept that the words can apply to both." The New Testament writers knew the Scriptures and related them to their own times, just as we do today. So Isaiah's words can apply to Isaiah's own time as well as to the first century and the 21st century.
Thank you for that insight, Chris! That clears up many questions we've had about Isaiah's prophecies about Immanuel and the verses that made it to Handel's Messiah.
I like Ellen's comment "I'm going to accept that the words can apply to both." The New Testament writers knew the Scriptures and related them to their own times, just as we do today. So Isaiah's words can apply to Isaiah's own time as well as to the first century and the 21st century.