A Large View of God
Certainly one of the key differences between the first phase of Isaiah (First Isaiah, or Isaiah of Jerusalem) and the second phase of the book (Second Isaiah) starting in chapter 40 is that a larger scope of God's action is in Second Isaiah. And in all places and all times spirituality and religion divide into those who hold a narrow view and those that see / imagine/ believe in a God of wide concern, love, and action.
In comic terms the person of narrow view prays,
"Dear Lord, Bless me, my wife, my farm -- these three and no more."
His faith no matter how sincere is focused upon a very few things that are close by. While devotion and loyalty to God may be strong, the scope of concern is highly limited. If of an unselfish frame of mine, he cares about his village, the healthy and the sick, the rich and the poor within it. But in geographic scope, his mind can barely move outside the county line.
Second Isaiah displays the wide view of God. God can work through leaders that are outside of the Hebrew people. Cyrus, King of the Assyrian empire can be called the servant of God, even in terms that suggest the Messiah. God can be imagined as standing about the "circle of the earth" looking down upon the nations. Here God has become large. The Sacred Presence is world wide.
We have left tribal religion. The Divine Life is no longer "the God of the hill country," or the God of the Jews.
In Second Isaiah we have stepped into a universal faith of a God so large that his concerns and actions touch all people in all places.