וְיִקְחוּ לִי תְּרוּמָה
That they bring for me an offering (Exodus 25:2)
In the Midrash (תנא דבי אליהו רבה) it is written that at the moment that Israel said (Exodus 24:7) "we will do and obey" (na'aseh v'nishma), the Holy One Blessed Be He immediately said that they should bring for Him an offering. And it appears to our master that this is based on what is said in the Midrash Rabbah (Exodus 42.8) for Ki Tisa:
R. Meir said: It was not even one complete day [before they sinned], for while they were yet standing near Sinai, exclaiming "We will do, and obey," their hearts were already concentrated on idolatry (כשאמרו ישראל נַעֲשֶׂה וְנִשְׁמָע מיד הרהרו ע"ז בלבם), for it says (Psalms 78:36): But they flattered Him with their mouth, and lied to Him with their tongue (וַיְפַתּוּהוּ בְּפִיהֶם וּבִלְשׁוֹנָם יְכַזְּבוּ לוֹ).
And our master has explained at length elsewhere that R. Meir follows his general opinion which is that the first expression dominates (תפוס לשון ראשון). Thus, when they uttered the word "נַעֲשֶׂה" (we will do) before they said "nishma" (נִשְׁמָע), i.e. understand, they showed that they wanted to perform an action before they would study and understand, because they despised study. For the reason that they committed the sin of the calf was that they refused to study in order that they themselves would understand the actions that they were obligated to do. That is why they asked (Exodus 32:1) for "G-ds, which shall go before us" (עֲשֵׂה לָנוּ אֱלֹהִים אֲשֶׁר יֵלְכוּ לְפָנֵינוּ) - so that, like a beast in the field, they could go and follow him without understanding or reflection. Thus, in saying "נַעֲשֶׂה" before saying "נִשְׁמָע", they exposed the vacuous idea that led to the sin of the calf. And had they not committed that transgression, it would never have been necessary for them to build the Tabernacle or to bring sacrifices, as we have written above (Seder Bo). Thus, the Midrash says that as soon as they said "נַעֲשֶׂה וְנִשְׁמָע" the Holy One Blessed Be He commanded them to take for Him an offering, which is derived from the connection between those words and the sin of the calf and the connection between the sin of the calf and the building of the Tabernacle. [See Seder Ki Tisa for further elaboration of this idea.]
וְיִקְחוּ לִי תְּרוּמָה מֵאֵת כָּל אִישׁ אֲשֶׁר יִדְּבֶנּוּ לִבּוֹ תִּקְחוּ אֶת תְּרוּמָתִי
That they bring for me an offering, from every man whose heart makes him willing you shall take my offering. (Exodus 25:2)
It may be asked why the words tikhu t'rumati (you shall take my offering) are repeated after the words "v'yikhu li t'rumah" (they shall bring for me an offering). And our master said something extraordinary about this. Rashi explains that the words "v'yikhu li t'rumah" mean that the offering should be taken "li-sh'mi" for My name. The later commentators explain that this is meant to teach that whatever charity and kindness a person does should be done for the sake of the Eternal alone Who commanded him to do so, rather than because his heart impelled him to do so and inspired him to do good and charitable deeds. For the good-hearted person, who opens his hand to everyone who asks without distinguishing between the deserving and the undeserving, will frequently waste his money on a person who is unworthy of charity, which is not good in the sight of G-d. So the best counsel for the person with a heart of flesh who lacks any constraint on his inclination to give to everyone with an outstretched hand is to give charity to an agent who collects funds that will be used for the sake of G-d and who will disburse them to the deserving poor that follow the path of the Divine Torah. That is why the Scripture says "v'yikhu li" (i.e., for My name) - to teach that those who give their money in the name of G-d (i.e., only to those who are deserving) may give the offering themselves. However from those whose heart impels them to give their money to anyone who asks them - from these you should take the money and distribute it appropriately only to those who are deserving.