For a lot of his life he wasn’t.
Has nothing to do with his faith. He was unhappy for a long time because He understood the Law and that living under the law there is no hope. When he understood Romans and justification by faith, the righteous shall live by faith, not in themselves or their works, he felt great relief. Later in life he felt depressed because of the stubborness of the German people, the Jews, and others to the Gospel and their continued desire to be under the law and have their works save themselves.
” Later in life he felt depressed because of the stubborness of the German people, the Jews, and others to the Gospel and their continued desire to be under the law and have their works save themselves.”
He was too impatient for change to happen.
Sounds a lot like modern day progressives.