“But Abram replied, ‘O Sovereign Lord, how can I be sure that I will actually possess it?’” - Genesis 15:8
We've read about Abraham's many acts of faith, even called the "Father of Faith" by some. In Hebrews 11, he left everything and moved his family to an unknown destination because the Lord told him to. We recall his act of obedience to sacrifice his only son on the mountaintop found in Genesis 22. Even in Genesis 15, he is recorded to believe God and counted as righteous because of his faith.
It would be easy to elevate Abraham in our minds as someone above us, higher than us, and somehow different than us because of his excellent displays of faith. However, Genesis also records his failures. From lying about his wife Sarah to having a child with his wife's servant, the Bible does not lie about his shortcomings.
Even after believing what the Lord told him in Genesis 15, we see he still questioned the Lord in verse 8, “how can I be sure that I will actually possess [the land]?” This passage and many others show he doubted and failed. Being a man of faith is about believing in what God says despite doubt and failure. If being “righteous because of [your] faith” is about being without doubt and failure, then it would be dependent on me.
A common covenant in those days between two people was to bring animals (Gen. 15:9) and split their carcasses in half. They would lay them out and then walk a torch between them to symbolize and finalize the covenant. God told Abraham to get the animals and divide them, but then put him to sleep before he could finish his part of the contract. But God sealed the covenant Himself by passing the torch between the halved carcasses while Abraham slept. (Gen. 15:17) This divine act was a symbol to Abraham that God would make his descendants as the stars in the sky. (Gen. 15:5) God would do it. Abraham’s part in the promise was to believe.
Abraham is recorded in Hebrews 11 as a man of faith because he believed God, not because his acts of faith outweighed or outnumbered his doubts, failures, or lapses of faith. His story comforts me because I have received from the Lord, believed, and walked in faith, but I have also doubted and failed as well. Our doubts and failures don't write our story, but our faith in Jesus does. Of all of those saints recorded in Hebrews 11, none were perfect and without fault, but they believed. As the Lord has told you, accept it and walk in obedience towards it.