Our Parsha is distinct in its beginning with a commandment relating to Aharon and his children. Rashi explains the form of this commandment, making use of the word "צו", with his famous comment: "אין צו אלא לשון זירוז מיד ולדורות." The word "צו" is meant to convey Zerizus, diligence, now and for future generations.
The Malbim explains that the word "צו" actually can be used to advance three ideas. One is לציין הזריזות, to underscore the need for acting with haste and without delay. A second intent is לציין התכיפות, to underscore the sense of immediate need, again implying that no delay should be allowed. A third is לציין שהמצוה נוהגת תמיד, to underscore that the Mitzvah is timeless and must be transmitted to future generations. These three ideas clearly parallel Rashi's brilliant three word explanation, mentioning ,מיד ,זירוז ולדורות.
It would appear, however, that the Malbim is not only clarifying the genius of Rashi, but also stating clearly that in general, a Korban, like an Olah or a Minchah, which gives no pleasure to the benefactor, must be brought truly Lesheim Shamayim, for the sake of Heaven. This means that it must of course have the elements of sincerity and purity, but it must also be done swiftly, immediately, and in a way that its underlying message may be transmitted for future use.
These same values may be extended to Mitzvos in general. Too often, we do a good deed, but it is only at our convenience or it is a momentary show of kindness, or it is a great idea for the future. The lesson of the Olah, as taught by the words "זאת תורת העולה" (ויקרא ו:ב'), is that service of Hashem must consolidate all three elements of diligence, immediacy, and continuity. This is the true meaning of Lesheim Shamayim.
Erev Pesach is an excellent example of a time when our efforts in preparing for the Yom Tov encompass these elements. The Torah states "ושמרתם את המצות," guard the Matzohs (שמות י"ב:י"ז), but the Midrash says that it may be read as ושמרתם את המצוות"," guard the Mitzvos, which teaches us מצוה הבאה לידך אל תחמיצנה, meaning, in effect, that we must observe all Mitzvos with diligence and without delay. This is certainly a message that must be passed on.
It is especially important for Bnai Torah to realize once again that "frumkeit" (Jewish piety) is not an act of convenience or the result of a momentary accident. Piety means righteousness and observance of ritual on a regular, on-going basis. There must be a sense of excitement and diligence to be a good person and to have Derech Eretz in the same way as there is excitement and diligence for the special moments of eating Matzoh and Maror. And this message must be transmitted לדורות, for all generations. The Talmid Chochom must be תוכו כברו, sincere and pious inwardly and outwardly, in the market-place and at home, in business and in Shul, with non-Jews and with fellow Jews, with non-observant Jews and with observant friends. This type of Lesheim Shamayim has the stamp of "צו" on it: לשון זירוז מיד ולדורות, a language expressive of diligence, immediacy and applicability for future generations.