Rav Yonason Eibeschutz zy”a (Sefer Tiferes Yonason) asks why it is forbidden to add on to Hashem’s mitzvos. He answers that we see from here that one shouldn’t make his own calculations when it comes to the mitzvos of the Torah. The Torah doesn’t need anyone’s approval, and no one is in a position to say that he knows what he thinks would be the right thing to do. Rather, one should simply do what Hashem commands, without any changes.
He compares this to a very sick person who summons a doctor to examine him and find out the source of his illness. The doctor checked him out and prescribed a medicine that would help him. However, he warned him to only take the prescribed amount – a little at a time. The patient reasoned to himself: If taking a little medicine at a time will help me, taking a lot will definitely help me much more!
Of course, he was gravely mistaken. Taking too much medicine at once would be extremely dangerous and could even kill the patient.
The same applies to mitzvos. If one adds mitzvos to what Hashem commands, he is placing himself in danger. The Torah is an elixir of life, but one can’t take more than the prescribed amount at one time. Hashem tells us how much we need, and it would be dangerous for us to decide to take more.
Anyone Who Adds is Decreasing:
The Dubno Magid zt”l (Mishlei Yaakov) explains with a moshol of a man who asks his neighbor to lend him a plate. The next day, he brings two plates to his neighbor. When asked why he is returning more than he borrowed, he answers, “Mazal tov! The plate you lent me had a baby!”
The next day, he borrows a spoon and returns two spoons, again explaining that the spoon had a baby. This went on several times with various utensils, much to the delight of the lender.
One day, the man asks his neighbor to lend him his expensive golden candelabra, which he wants to use to illuminate his home for the guests he was expecting. Of course, the neighbor is happy to give it, as he hoped to get two golden candelabras in return.
The next day, when the neighbor asks for his candelabra back, the man apologetically says, “I hate to tell you this, but the candelabra died.”
The neighbor begins to scream, “Are you serious? Everyone knows that a candelabra can’t die!” But the man replies, “You accepted it when I said that your plate and spoon had babies, so why can’t you believe that a candelabra can die?”
When one adds mitzvos to the Torah, he is akin to this man. He is claiming that a mitzvah can “have a baby” by increasing to it. But if one does this, he may also claim that another mitzvah “died” and he doesn’t have to fulfill it. Thus, the Torah is saying that one may not add on it to the torah because he may end up decreasing from it as a result.
