This week's Torah reading teaches us a very practical law. The Torah tells us that if a person is building a new house, he is obligated to make sure there is a fence around the roof to eliminate the danger of someone falling off it (Deuteronomy 22:8).

This is, of course, an admirable idea — the idea of neighborly responsibility, of not being negligent even on one's own property because another person may come to harm, and so forth.

The Torah goes further, however. The verse uses an interesting phrase — ki yipol hanofeil mimenu — which means, literally, to make a fence around the roof "lest somebody who is prone to falling should fall off it."

If the person is going to fall anyway, why should I have to take precautions? Yet this law is taught specifically regarding one who is a "faller."

There is, as ever, the commentator Rashi, who explains that even though it may be Divinely ordained that this person will fall anyway, you should not be the one to bring it about.

On a deeper level, it is a very powerful lesson for all aspects of our lives. Many times we are tempted to take advantage of another person. Often the excuse is that "he's asking for it." Children in the playground will pick on another child, arguing that he makes himself a natural victim. Global powers will do the same thing on an international level. Unfortunately, there is a perception that because someone has a weakness, this is automatically grounds to take advantage of him or her.

The Torah is telling us that this is not acceptable. Even regarding one who is going to fall anyway, you must take precautions to help prevent him from doing so rather than letting him become a victim of his own weakness. Not only are we commanded not to take advantage of that person, but we are actually commanded to do everything in our power to help him.