God made a covenant with Abram. That’s an agreement with an “I swear” promise. In Abram’s time, each person would promise something to the other. Then they’d walk between cut up animals and swear that they would be cut up too—killed—if they didn’t keep their covenant promise.
But God didn’t make Abram promise anything. God passed through the cut up animals alone. He took all the risk.
God swore to give much to Abram’s descendants. All Abram did was believe. Because he believed, God counted it as if Abram did what was right (righteousness).
It’s a good thing Abram didn’t have to walk through the animals and promise to always live God’s way. He was a sinner just like us. He couldn’t earn righteousness. He needed the kind of righteousness God gives and counts to us even though we don’t earn it.
Like with Abram, God takes all the risk in his covenant with us. We don’t always live God’s way, but Jesus is the only one to die. We believe in Jesus, and God counts us as righteous!