God tells Abram to do so in order to impress him with the generosity of His promise to Abram. It's still a wonderful invitation to prayer to our transcendent God.
In short order, we will hear about the Suffering Servant, our God who was mocked, spat upon, bound, scourged and led to crucifixion. During the events of Holy Week, the transcendent power of our God may seem hard to find.
The God of Abram drew close enough to enter into a covenant with him. In our New Covenant with God, Jesus not only draws near, but becomes one of us.
Pray under the stars this Lent. It brings gratitude and humility.
Image from the Hubble telescope.