Today God walks a childless old man outside and says: count the stars. So shall your offspring be. And Abram believed the LORD, and it was credited to him as righteousness.

Hold that sentence while Jesus preaches the second half of Matthew 5, where the standard climbs all the way to be perfect, as your heavenly Father is perfect. The two passages need each other. Read them together.

Matthew 5 ends at an altitude no one can climb: be perfect, as your heavenly Father is perfect. If that sentence were the whole gospel, it would only produce despair or pretending. Genesis 15 is the oxygen: Abram believed the LORD, and He credited it to him as righteousness. Faith, counted as the very thing we lack.

And notice who sealed the deal. Abram slept while God alone passed between the pieces, taking both sides of the covenant onto Himself. That is still the arrangement. Aim at everything Jesus preached today, love enemies, guard the heart, walk the second mile, and do it as someone already credited, not someone still auditioning.