An excerpt from Shmooze: A Guide to Thought- Provoking Discussions on Essential Jewish Issues

Life is precious. Any decision must reflect its infinite value.

Let's be practical. By murdering one person, you save millions of lives from cancer. By sparing him, you save only one person -- one ninety-year-old person who has already lived out the prime years of his life. In this instance taking one life saves millions. If we value life, surely this is the right decision.

Yet most of us intuitively know this can't be right. It's wrong to murder an innocent ninety-year-old, even if it would guarantee a cure for cancer.

Can you explain why?

Unfortunately, this dilemma is not just theoretical. In the book Holocaust and Halachah, a concentration camp inmate asked a rabbi the following question:

"The Nazis have imprisoned 100 children who they plan to murder tomorrow morning. My son is among them. I can bribe the guard to free my son, but if I do the Nazis will grab someone else's son to replace mine. Rabbi, may I bribe the guards to free him?"

The rabbi refused to answer. From his silence, the father derived the rabbi's answer - he was forbidden to free his son at the expense of someone else's life.

The Talmud, discussing a similar predicament, states, "How do you know your blood is redder? Maybe his blood is redder?" Rashi, commenting on the Talmud, elucidates: "Who knows that your blood is more precious and more dear to your Creator than the blood of someone else?" How can one weigh the value of one life against the value of another? How can one know which person is more precious? Each individual is an entire world.

That makes sense when dealing with one life versus another. But how does it explain saving one life at the expense of millions? Can't we say with confidence that in God's eyes millions of lives are more precious than one?

At the heart of this issue is how one measures the value of life.

A story is told of a rabbi and a thief who enter Heaven. The thief is singled out for his tremendous accomplishments and receives royal treatment. The rabbi is viewed as Mr. Average.

How can a thief be considered greater than a rabbi who devoted his entire life to the community, doing many acts of kindness and living an honest, decent life?

Every person is born with a unique personality and set of circumstances, as well as a certain amount of potential for growth. Where we begin is beyond our control. However, we are responsible for where we end up and the choices we make along the way.

Perhaps the rabbi was blessed with every advantage -- born to loving parents who provide him with the best schooling and a wholesome upbringing. Perhaps he possessed tremendous intelligence, compassion and a good-natured personality. Perhaps his father served as a community rabbi and he naturally chose the same calling. His true worth is not measured by how he began his life. He did not work to attain his inborn strengths (and weaknesses), and so they are not intrinsic to his true essence. They provide the backdrop for his unique challenge to strive for personal greatness. His real worth is the result of the choices he made in his effort to grow. Determining the value of his life requires taking every factor and detail of his existence into account.

On the surface, the rabbi appears to be greater than the thief, perhaps even greater than many other people. But when you consider the larger framework, from his starting point in life to the potential greatness he could have reached, a different picture emerges.

This rabbi coasted through life, choosing mediocrity. With more perseverance, he could have accomplished much more.

Let's say the thief was born with tremendous disadvantages - a violent temperament, abusive parents, no money and low intelligence. None of this determines his true worth. His essence consists of the choices he made within his unique playing field.

The thief decided to build a better life for himself. He struggled to conquer his inner demons and got a job to work his way through college. When things got rough, he turned to stealing to make ends meet. But he consistently strove to be an upstanding member of society, to raise a healthy family, and to make a meaningful contribution to the world.

When we compare the degrees of personal growth of both the thief and the rabbi, it becomes clear that the thief is the greater individual.

Of course this example is a gross oversimplification. The complexities involved in making such a judgment are staggering -- which is exactly why no human being is in the position to judge the worth of another. No one knows the challenges of another person, or his potential, or what the Almighty expects from him. We can never measure someone's true value. That is God's business alone. It is never a good idea to play God.

This doesn't justify the thief's actions. Stealing is wrong and must result in certain consequences. We can judge the thief's actions, but not his worth. These two judgments are separate, the former belonging to man and the latter belonging only to God. We can't know how God views the worthiness of the thief.

Therefore, when it's millions of lives versus one ninety-year-old man, maybe that one life is more precious and dear. How can we know? The issue has nothing to do with numbers. The judgment is not ours to make, no matter how many lives are involved.

Rabbi Nechemia Coopersmith is the Director of Research and Development for Aish HaTorah and is Managing Editor of aish.com. He lives with his wife and children in Jerusalem.         `copyright aish.com`