The answer is: Sarai

Genesis 17:15 - God changed Sarai's name to Sarah when He reaffirmed His covenant with Abraham, signifying her new role as the mother of nations.

Before she became known as Sarah, the beloved wife of Abraham was indeed called Sarai. Interestingly, the name Sarai is often understood to mean "my princess," a title reflecting her importance in Abraham's life. However, when God changed her name to Sarah—meaning "mother of nations"—it didn’t just signify a change in title; it was indicative of her God-ordained purpose. This moment represents a turning point where not just Abraham but also Sarah took on significant roles in the fulfillment of God's plans for humanity.

Sarah's transformation also showcases how names in the ancient world carried profound meanings and significance. Throughout the Bible, names often reflect divine intentions. Think of Jacob, whose name meant "supplanter" and later became Israel, meaning "wrestles with God." Similarly, Abram became Abraham, meaning "father of many nations."

Another fascinating bit about Sarah's faith journey is that she was noted for her laughter in Genesis 18. When she overheard the prophecy that she would have a son at her old age, she laughed—a mix of skepticism and delight. This points to a universal truth: even the faithful wrestle with doubt. Her story is a beautiful reminder that regardless of our doubts or age, the potentials for re-birth and impact can emerge in the most unexpected of times and circumstances.