Genesis 15:1 - After these things, the word of the Lord came to Abram in a vision, saying, "Do not be afraid, Abram. I am your shield, your exceedingly great reward.
In the previous chapter, Abram conquered nations that belonged to 4 kings to save his nephew Lot. Most likely, Abram was afraid of these nations recruiting others and getting revenge on Abram.
God personally spoke with Abram. God knew his fears and let Abram know not to be afraid. God promised to protect Abram (I am your shield).
I believe God speaks to us personally. God knows our fears and promises to protect us.
If you find yourself worrying about what lies ahead, dwell on the fact that God is with you, and he has promised to bless you.