[AndyTheBear]

Just to be sure I wasn't mistaken, I looked up the verse in Isaiah where he calls himself a prophet:

Then Isaiah the prophet went to King Hezekiah and asked, “What did those men say, and where did they come from?”
“From a distant land,” Hezekiah replied. “They came to me from Babylon.” --Isaiah 39:3 (NIV)

I don't know if the Hebrew phrase for "Isaiah the prophet" was the same as the the Hebrew on the seal, but at least the translation to English in this article and from the NIV bible match.

[AndyTheBear]

Correction, I accidentally implied the narrator was Isaiah, but I am under the impression the scrolls of Isaiah were being written down for him by one or more scribes.