Fearlessness through faith is the theme of Devarim.
G-d and Moshe repeatedly tell the Jews not to fear. Indeed the conclusion of Devarim declares, "Do not fear them, for it is the Lord G-d that fights for you."
Why are the Jews repeatedly being told not to fear?
Devarim begins with the failed journey from Mount Sinai to Israel. That journey is aborted by the fear of the conquest. The Jews turn on Moshe and on G-d. And they are exiled to wander in the desert for 40 years. Now the Jews are once again told to advance and conquer, without fear.
Why is this generation more fit for the task than the one that left Egypt?
The Parsha uses two very similar phrases. First, at Har Sinai, "You have dwelled long enough in the mountain, turn and journey..." (Devarim 1:6) Then, after wandering in the desert, "You have spent enough time circling this mountain, turn around..." (Devarim 2:3) That second mountain is Har Seir.
The contrast could not be greater between Mount Sinai, the mountain of G-d, and Mount Seir, the essence of Edom and exile.
After a little time of dwelling at Har Sinai, of living in comfort, the Jews no longer had the determination and the fearlessness to conquer Eretz Yisrael. They had been dwelling in the ultimate place of faith, they had seen the miracles of the Ten Commandments, and yet they lacked faith when it came to an arduous challenge.
But after wandering for forty years in the desert, of being flush against Har Seir, the mountain of the ultimate enemy, of living in exile, they did have the faith to conquer and prevail.
Devarim begins with a curious phrase. Hoyil Moshe Be'er et Hatorah Hazot. Moshe began to expound the Torah.
We would expect the recitation of the Ten Commandments to follow. But that comes later. Or at least some laws. Instead Moshe discusses the departure from Sinai and the journey to Israel.
You have dwelled long enough in the mountain, turn and journey..."
How can the Torah begin where it seemingly ends? But the Torah truly begins when you put it into practice. When you measure it against the world, as the Jews did, and either succeed or are found wanting. Tests of faith determine whether our learning is meaningful or rote.
Moshe's recitation of the Torah begins with the first test of the Jewish people. After learning and living in peace, they lacked the faith to be fearless. It was only after they endured the exile, that they had the faith to overcome the fear. Only then could they truly believe that G-d would fight for them.
When you grapple with Edom, you can truly believe that G-d can help you overcome.
Fearlessness requires experience with fear. Faith requires tests.