God understood the ways of man very well. He knew the nations that would concur Israel would get His people to worship Idols instead of staying faithful to God their redeemer. But because Isaiah sought the LORD and asked God to send Him (Isaiah 6:8) God used Isaiah mightily to give His people the messages from the LORD. Isaiah is also considered the 5th Gospel, this is because He receives and shares the birth of the Prince of Peace (Isa 9:6), The servant who suffered for our transgressions (Isa. 53), and the call to repentance through conviction and confession throughout the Book. Isaiah was not a prophet for selfish gain but a servant of the most High to bring us to full salvation under our risen King Jesus.