Romans 4:13-16

God promised Abraham and his descendants that they would have an heir who would reign over the world. This royal promise was not fulfilled because Abraham kept all the law, but through the righteousness that was transferred by faith. For if keeping the law earns the inheritance, then faith is robbed of its power and the promise becomes useless. For the law provokes punishment, and where no law exists there cannot be a violation of the law. The promise depends on faith so that it can be experienced as a grace-gift, and now it extends to all the descendants of Abraham. This promise is not only meant for those who obey the law, but also to those who enter into the faith of Abraham, the father of us all.