Isaiah’s second half is full of hope and promises. The seeds of the Gospel can be found all throughout. What I find most fascinating is that Isaiah seems to be lamenting about his failure to bring Israel back to repentance. And just as Isaiah says that he finds his strength in God to do the impossible task of preaching to Israel, God blows his mind by enlarging the task and sending him off to all nations. See this passage for example:
5 “And now,” GOD says,
this God who took me in hand
from the moment of birth to be his servant,
To bring Jacob back home to him,
to set a reunion for Israel–
What an honor for me in GOD’s eyes!
That God should be my strength!
6 He says, “But that’s not a big enough job for my servant–
just to recover the tribes of Jacob,
merely to round up the strays of Israel.
I’m setting you up as a light for the nations
so that my salvation becomes global!”
7 GOD, Redeemer of Israel, The Holy of Israel,
says to the despised one, kicked around by the nations,
slave labor to the ruling class:
“Kings will see, get to their feet–the princes, too–
and then fall on their faces in homage
Because of GOD, who has faithfully kept his word,
The Holy of Israel, who has chosen you.”