The book of Isaiah follows the Jewish people during their exile from Babylon. Times were tough: the city of Jerusalem was destroyed by the Babylonian king, Nebuchadrezzar, and the Jewish people were enslaved for decades.
In Isaiah 40, there is a light at the end of the tunnel. The Jewish people are permitted to return to Jerusalem, ending their exile, but a long trek is ahead of them.
With this context in mind, I believe Isaiah 40:11 begins to make a lot more sense.
What is the longest walk you have ever been on? How about the longest walk in the summer in the desert?
Now imagine that you don't know when you will arrive, what will be there when you arrive, and that each day brings you to a new place that you have possibly never been before.
Imagine the fear you would feel, the insecurity you would be wracked with on a daily basis, and the anxiety you would feel towards the unknown you would encounter every single day.
There is an answer, however, a guiding hope that will lead you when you are lost. It is the Lord our Shepherd.
This imaginary exercise can only paint a very loose picture of what the exiles of Jerusalem were truly feeling. They were enslaved for decades, broken and tortured, split from their families and had their faith decimated.
They continued to trust in God, and God never abandoned them.
The rejoicing tone of this verse can be easily felt. Wandering in the desert, tired and lost, the Jews are finally allowed to return home.
Their faith wavered, their will was tested, but God fed his flock, gathered and carried them, and gently led those with children.
A shepnherd can carry a baby lamb and will see the mother of the baby follow closely, the most intimate and gentle experience that a shepherd can perform.

