The answer is: 100

Genesis 21:5 - Abraham was 100 years old when Isaac was born, showcasing God's promise fulfillment despite natural impossibilities. Interestingly, this miraculous birth points to the New Testament's message of new beginnings through Christ, who mirrors Isaac’s story as a child of promise (Romans 4:19-21).

Abraham’s age when Isaac was born, a remarkable 100 years, stands as a testament to the awe-inspiring ways in which hopes can blossom against all odds. Picture Abraham, a figure known for his faith, who believed even when reason said “no.” This moment in Genesis captures the essence of new beginnings, illustrating that life's impossible dreams can indeed come to fruition when fortified by hope and unwavering trust.

Interesting trivia - Isaac’s name itself means “laughter,” reflecting Sarah’s initial reaction to the astonishing news that she would give birth at such an advanced age (Genesis 18:12-14). Can you picture the joy and disbelief mixed into each joyous laugh she roasted around the hearth? Isaac’s narrative not only introduces the concept of new life but also resonates throughout the biblical accounts as he is considered a pivotal link in the lineage leading to years down the line to Christ.

Drawing parallels, in the New Testament, the advent of Jesus is often associated with births of divine promise, invoking themes of renewal that resonate with our own lives today. Just as Isaac represents a fresh beginning in God's covenant, the coming of Christ heralds a new era of hope for humanity. This cycle of spiritual rebirth invites each of us to embrace our own transformations— no matter the mountain in front of us. With belief underscoring challenges, miracles enter the mundane, setting the stage for life’s greatest surprises. So next time you're facing doubts, remember Abraham and Sarah's laughter—the triggers of new destinies waiting to unfold!