What does Genesis 15:1 mean?

After all this, God spoke to Abram in a vision: Don’t be afraid, Abram. I’m your shield, and I’m the one who will reward you—more than you can imagine. Genesis 15:1 - Modern Text Bible

(God reassures Abram, promising protection and a reward that goes beyond material wealth. The focus is on God’s relationship with Abram, not just what Abram gets.)