“Here I am! Send me,” came the ready response. The speaker was Isaiah, who had already been prophesying before this. It was the year that leprous King Uzziah died, about 778 B.C.E. (Isa. 6:1, 8)

He served during the time of at least four kings of Judah: Uzziah, Jotham, Ahaz, and Hezekiah; evidently beginning about 778 B.C.E. (when Uzziah died, or possibly earlier) and continuing at least till after 732 B.C.E. (Hezekiah’s 14th year), or no less than 46 years. No doubt he had also committed his prophecy to writing by this latter date. (1:1; 6:1; 36:1)