Although generally we are told what we must and what we must not do, there are some concepts and attitudes that the Torah expects us to know without being told. These are so fundamental that that in their absence, the mitzvos we do are essentially crippled.
In Greek, the word Meta means after or beyond. In English, it can be used to mean a fundamental truth beyond the self-evident, an abstraction that transcends and informs the reality with which it is associated. It is both transcendent and fundamental.
Our 613 Mitzvos are defined clearly enough for us to know exactly whether we have or have not fulfilled them. But there are meta-Mitzvos. By this I mean an underlying attitude or a manner beyond the legal definition of any particular Mitzva. Even if one fulfills a mitzva, he may have failed in the Meta-Mitzva. Sometimes, failing the Meta is worse than not doing the Mitzva at all.
Here's an illustration: Reb Chaim's pshat in Kavanas Hatefilla. Reb Chaim says that more fundamental than the Kavana of "what the words mean" is the Kavana of "standing before the King." Even if you could get away with mouthing words and not thinking about what they mean, you cannot be said to be davening at all unless you are aware that you are standing before Hashem. That, to me, is Meta-Kavana.
Three examples of Meta-Mitzvos come to mind.
1. The Yerushalmi (Brachos 2:5) says that a laborer who eats during his work day cannot say the usual long form of Bentching, but instead says the first bracha and a shortened version of the rest. The Yerushalmi says that even though we all are able to work while we bentch, this is prohibited. Because it is assur to work while you Bentch, the only option is to truncate Bentching,
The Taz (OC 191:1) says that this is true by all tefillos and by all mitzvos:
2. What is worse, occasionally being Mechallel Shabbos, or scrupulously keeping Shabbos but not believing that Shvisa is a mitzva from the Ribono shel Olam?
In Devarim (27:26) it says אָרוּר אֲשֶׁר לֹא יָקִים אֶת דִּבְרֵי הַתּוֹרָה הַזֹּאת לַעֲשׂוֹת אוֹתָם
Cursed is he who does not uphold the words of this Torah to do them. The Ramban explains this to pertain to a Jew who does all the mitzvos, but does not believe in his heart that the mitzvos are divine obligations, that Hashem rewards their observance, that Hashem punishes their desecration. The Ramban says that if a person does the mitzvos but doesn't believe they are min hashamayim, then he is subject to the curse. If, on the other hand, a person simply violates commandments, that is, a person who eats chazir or does not keep the mitzva of Sukkah or lulav, but still believes they are true and that ultimately there is reward and punishment, that person is not subject to the curse in the parsha. In other words, it is worse to do mitzvos but not believe they are from Sinai than to not do them but know that you are being a sheigitz. (See the words of the Ramban below.)
This, by the way, should give pause to those that believe that Judaism is a religion of actions, Orthopraxy, and that belief, Orthodoxy, is not so important. Unless, of course, they disagree ("He's a Rabbi, and I'm a Rabbi") with the Ramban.
3. Devarim 28:47, תַּחַת אֲשֶׁר לֹא עָבַדְתָּ אֶת יְהוָה אֱלֹהֶיךָ בְּשִׂמְחָה וּבְטוּב לֵבָב. A person does all that is expected from him; but he does it grudgingly and resentfully, feeling that Mitzvos are an imposition he would prefer to be without. This is a sin that can chas ve'shalom tip the balance to the tochecha. Imagine that! The attitude makes such an enormous difference! I remember hearing Reb Shalom Shvadron speak about this on the psukim in Malachi 3:13-14. חָזְקוּ עָלַי דִּבְרֵיכֶם אָמַר יְהוָה. וַאֲמַרְתֶּם מַה נִּדְבַּרְנוּ עָלֶיךָ. אֲמַרְתֶּם .שָׁוְא עֲבֹד אֱלֹקְים וּמַה בֶּצַע כִּי שָׁמַרְנוּ מִשְׁמַרְתּוֹ וְכִי הָלַכְנוּ קְדֹרַנִּית - The people said "It is futile to serve God, and what profit do we get for keeping His charge and for going about in anxious worry ( because of Hashem's commandments)." Rav Shvadron asked, how can the people say "what did we say that was wrong?" And the Gemara says that not only the people were clueless, even the Malachim didn't understand why Hashem was upset. If they said shav avod Elokim, if they said ma betza, if they said halachnu kedoranis, it should have been obvious that there was a problem. The answer is that they did every mitzvah, they did everything with hiddur, but they did it with sour faces and an attitude that the mitzvos were a burden. They didn't chas veshalom say a negative word about the mitzvos, but their faces and slumped shoulders screamed out their dislike of the mitzvos.
Summing up, I say that there are three Meta-Mitzvos: Reverence, Awareness, and Joy.
1. Respect and reverence that focuses your attention exclusively on the Mitzva while you do it.
2. Awareness that this Mitzva is Hashem's will as He taught us in His torah min hashamayim, and that we do the mitzvos because we are obligated to do as Hashem commands us.
3. Joy that we have the opportunity to serve Hashem in a way that makes us into great and holy people.
Slightly off topic: We find a similar idea in the context of Kibbud av. Devarim 27:16, אָרוּר, מַקְלֶה אָבִיו וְאִמּוֹ. Cursed is he who belittles his parents. Reb Meir Simcha in his Meshech Chochma- explains that this is a person who belittles his parents because he knows they will be mochel. Mechila might help; this person has not transgressed the mitzva of Kibbud. He's not even like the Ma'achil petumos veyoreish Gehinom, because here, the parent is mochel. But that doesn't help him. His disparaging attitude is as great a sin as actual bitul asei.
Comments about the Ramban made it clear that I ought to quote it verbatim.
Also, please note that we're not quoting a Gemara or a Medrash. This is a Taz, a Ramban in his pirush al hatorah, and a diyuk in a passuk.