What potential monetary loss could there be in bringing a sacrifice?
(6.2) “Command Aharon and his sons, saying: This is the law of the burnt-offering, it is that which goes up upon the firewood upon the altar all night until the morning, and the fire of the altar will burn with it.”
Rashi explains: The word צו always denotes urging for the present and for future generations. Said Rabbi Shimon: The Torah especially needs to urge where monetary loss is involved.
In order to explain this Rashi, let us first explain the words of Shlomo Hamelech in Koheles 7:23: “I said I will be wise, but it is far from me”. What is the explanation behind Shlomo’s choice of words - “but היא is far from me”?
We can explain his choice of words from the gemora which teaches that one who says [about an animal] “behold, it is upon me a burnt-offering”, if it gets lost or something else prevents him from bringing it, he is responsible for it [and has to bring another in its place] since he said “it is upon me”. But if he says “behold, this is a burnt-offering” he is not responsible for it. And another gemora teaches that one is responsible for a Red Heifer, as it says “for sprinkling water, חַטָּאת הִוא” - it is subject to all the laws of a sin-offering, [including the fact] that he is responsible for it.
This is what Shlomo Hamelech was saying: “I said I will be wise” and know the reason why one is responsible for the Red Heifer, and it must be because it says “for sprinkling water…היא”. “But היא is far from me”, because on the contrary, if a person says זו or he says היא, we have established that he is free from responsibilty! Therefore, understanding it is far from me.
Now we can understand our posuk: “Urge Aharon and his sons, saying: This is the law of the burnt-offering” - the law of a burnt-offering that one is not obligated to bring another one [if something happens to the first one] - use the word זאת. And if you do use the word זאת, then behold, “הִוא הָעֹלָה” - only this is the burnt-offering.
But why was he told to do this? The answer is the teaching of Rabbi Shimon: The Torah especially needs to urge where monetary loss is involved [to ensure that the person will not need to bring another offering if something happens to the first one].