The purpose of this is to remind us to have a life that encounters God at every turn. We begin with blood, which consacrates, also brings tum'ah whitin it - because it symbolizes the life force of the being.
Service of imagination - the laying of hands on an animal, sensing its life, and then seeing it being killed and having its warm blood smeared on oneself. Ear / earmarked, making sacred what one hears; thumb making sacred what you touch and how you touch; big toe, the locus of balance and walking, making sacred your comings and goings.
Now we are doing prayer alone - dispute to connect it with patriarchs or sacrifices is well-known - but tefilah from p.l.l. see Yaakov talking to Yosef, to imagine, to think, to actually see in all its glory, to pay attention. Not as common usage in other languages, including English, pray = request. Connection and awareness. Which is the primary purpose of sacrifice, and maybe we flinch, and dislike it, but it worked way back when: Korban = mekarev - Rashi and midrahsh Yalkut Shimeoni
In Aaron's case, and in his sons' case: they feel that their life is actually given as a gift. They experience it: put the hands on this animal, not a small one, a ram.
But we are all priests - mamlechet kohanim vegoy kadosh - How can we anoint what we hear, what we touch, and how we walk in the world so that our lives are a vehicle of awareness that everyone's life-force is borrowed from God?
In that sense, our reading of Jeremiah (this haftarah) is revisited: not "obedience but not sacrifices"; but "obedience and sacrifices". Jeremiah's question is - what are you doing, thinking that the externalities are the only thing that count? Everything counts! Everything we do should be with awareness of God! Martin Buber agrees, as does Shai Held.
איתמר רבי יוסי ברבי חנינא אמר תפלות אבות תקנום רבי יהושע בן לוי אמר תפלות כנגד תמידין תקנום תניא כוותיה דר' יוסי ברבי חנינא ותניא כוותיה דרבי יהושע בן לוי תניא כוותיה דרבי יוסי בר' חנינא אברהם תקן תפלת שחרית שנא' (בראשית יט, כז) וישכם אברהם בבקר אל המקום אשר עמד שם ואין עמידה אלא תפלה שנאמר (תהלים קו, ל) ויעמד פינחס ויפלל יצחק תקן תפלת מנחה שנאמר (בראשית כד, סג) ויצא יצחק לשוח בשדה לפנות ערב ואין שיחה אלא תפלה שנאמר (תהלים קב, א) תפלה לעני כי יעטף ולפני ה' ישפוך שיחו יעקב תקן תפלת ערבית שנאמר (בראשית כח, יא) ויפגע במקום וילן שם ואין פגיעה אלא תפלה שנאמר (ירמיהו ז, טז) ואתה אל תתפלל בעד העם הזה ואל תשא בעדם רנה ותפלה ואל תפגע בי ותניא כוותיה דר' יהושע בן לוי מפני מה אמרו תפלת השחר עד חצות שהרי תמיד של שחר קרב והולך עד חצות ורבי יהודה אומר עד ארבע שעות שהרי תמיד של שחר קרב והולך עד ארבע שעות ומפני מה אמרו תפלת המנחה עד הערב שהרי תמיד של בין הערבים קרב והולך עד הערב רבי יהודה אומר עד פלג המנחה שהרי תמיד של בין הערבים קרב והולך עד פלג המנחה ומפני מה אמרו תפלת הערב אין לה קבע שהרי אברים ופדרים שלא נתעכלו מבערב קרבים והולכים כל הלילה ...
It has been reported : R. Jose b. R. Hannina said : The Patriarchs instituted the Tefillot. R. Joshua b. Levi said: The Tefillot were instituted to correspond with the continual sacrifices. There is a teaching in agreement with both of them. There is a teaching in agreement with R. Jose b. R. Hannina: Abraham instituted the morning Tefillah; as it is said, "And Abraham got up early in the morning to the place where he had stood" (Gen. xix. 27) — "standing" means prayer; as it is said, "Then stood up Phineas and prayed" (Ps. cvi. 30). Isaac instituted the afternoon Tefillah; as it is said, "And Isaac went out to meditate in the field at eventide" (Gen. xxiv. 63) — "meditation" [sihah] means prayer; as it is said, "A prayer of the afflicted when he fainteth, and poureth out his complaint [sihah] before the Lord" (Ps, cii. 1). Jacob instituted the evening Tefillah ; as it is said, "And he lighted [paga'] upon the place, and tarried there all night" (Gen. xxviii. 11) — "alighting" means prayer; as it is said, "Therefore pray not thou for this people, neither lift up cry nor prayer for them, neither make intercession [paga'] to Me" (Jer. vii. 16). There is also a teaching in agreement with R. Joshua b. Levi : Why is it declaimed: The morning Tefillah [may be said] until midday ? Because the morning continual offering could be brought until midday. R. Judah says : Until the fourth hour, because the morning continual offering could be brought until the fourth hour. And why is it declared : The afternoon Tefillah [may be said] until the evening? Because the twilight continual offering could be brought until the evening. B. Judah says : Until the middle of the afternoon, because the twilight continual offering could be brought until the middle of the afternoon. And why is it declared : As for the Tefillah of the evening, it has no fixed time? Because the limbs and the fat which had not been consumed by the evening may be offered at any time during the night. And why is it declared : The additional Tefillah [may be said] at any time in the day? Because the additional offering could be brought at any time during the day. ...
(ט) תפלות אלו אין פוחתין מהן אבל מוסיפין עליהם אם רצה אדם להתפלל כל היום כולו הרשות בידו וכל אותן התפלות שיוסיף כמו מקריב נדבות לפיכך צריך שיחדש דבר בכל ברכה וברכה מן האמצעיות מעין הברכות ואם חידש אפילו בברכה אחת דיו כדי להודיע שהיא נדבה ולא חובה ושלש ראשונות ושלש אחרונות לעולם אין מוסיפין בהן ולא פוחתין מהן ואין משנין בהן דבר.
(י) אין הציבור מתפללין תפלת נדבה לפי שאין הציבור מביאין קרבן נדבה ולא יתפלל אפילו יחיד מוסף שתים אחת חובת היום ואחת נדבה לפי שאין מתנדבין קרבן מוסף ויש מן הגאונים מי שהורה שאסור להתפלל תפלת נדבה בשבתות וימים טובים לפי שאין מקריבין בהן נדבה אלא חובת היום בלבד.
(9) One may not subtract from this [number of] prayers, but if one wishes, one may add to them. One can even pray all day long, if one so desires. These additional prayers are comparable to voluntary sacrifices [offered at the Temple], and one must therefore make an innovation in each of the middle blessings [of the Amidah], paraphrasing the [original] blessing. Even if one makes an innovation in a single blessing, this is sufficient to show that it is a voluntary prayer, rather than an obligatory one. Yet the first three and last three [blessings] are never added to or subtracted from, and nothing in them is to be changed.
(10) A voluntary prayer may not be recited by a community, just as the voluntary sacrifice was never a public one. Similarly, an individual may not pray the Mussaf prayer twice, once to fulfil his obligation and the other voluntarily, since the Mussaf sacrifice was not offered voluntarily. In addition, some of the Geonim ruled that additional prayers were not to be recited on Shabbat and festivals, since voluntary sacrifices were not offered on those days, but rather only the obligated offerings of that day.
On Buber's Thought
In the dialogue between God and man, "God speaks to each man through the life He has given him and in which He upholds him. And the only way in which man responds to Him is with his whole life " in the way he lives it." The Jewish teaching of the unity and oneness of God corresponds to its teaching of the oneness and all-inclusiveness of life. God gives man not merely spirit but existence in all its parts, from the lowest to the highest. Man's partnership with God cannot be confined or reduced to mere "spiritual" attitudes, to devout feelings or a superstructure of ritual practices. It requires his whole life, in all its aspects and relationships. Man can have no real part in holiness without the sanctification of his every-day life.The history of Judaism discloses that it has always opposed so-called "religion" because it has seen in it the attempt to buy off God, who demands all, with a limited segment of life. (Bergman, Samuel Hugo. pp. 94-5. Faith and An Introduction to Modern Jewish Thought. London: Forgotten Books.)
Shai Held
Our hypocrisies may (sometimes) be more subtle than ancient Israel’s, but they are no less real. In this day and age, God may not actually kick us out of the synagogue, but God may abandon us there, leaving us alone with our hypocrisy and cant.
Jeremiah is not opposed to the sacrificial system laid out in parashat Tzav, or to ritual in general. But he is intensely worried that sacrifice and ritual can be used in hypocritical, counter-productive ways.
Prayer Instead of Sacrifice, Natan Aviezer, Bar-Ilan University, Tzav 2014
What is the object of prayer? Some will say that it is our way of addressing the Holy One, blessed be He, so that He will respond favorably to the petition of the person praying and help that person, both in time of trouble and in providing their daily needs. But if we delve a bit further into the matter, we see that this perception of the essence of prayer can hold only if the Holy One, blessed be He, is likened to a king of flesh and blood. A mortal king is not aware of the needs of each and every one of his subjects, and therefore these needs must be specified to him.
Is it necessary for us to do so also when addressing the Holy One, blessed be He, as if He did not know our needs and troubles? Does a "reminder" have to be sent three times a day? Clearly prayer, which plays a considerable part in Judaism, is quite a different matter. Its primary objective is to remind us that all that we have comes from Him. We are the ones who have need of prayer, as many commentators have noted.[1] The purpose of prayer is to remind us, time and again, of our utter dependence on the beneficence of the Holy One, blessed be He, and to help us focus on building a stronger tie with the Creator.
This sense of prayer also finds expression in the Hebrew root of the word. In all European languages the word denoting prayer means to request or petition (beten in German, prier in French, and молиться in Russian), whereas in Hebrew, the root p-l-l means to call to mind or bring to attention
[1] For example, Nahmanides, in his interpretation of Ex. 13:16 (near the end); Sefer Ha-Hinukh, commandment 430, "Benedictions" (in the reasons for the commandment); "Ma-hi Tefillah?," Siddur Otzar ha-Tefillot, Vilna 1914, Preface to Part I, pp. 8-11.
The notion of being near to the Holy One, blessed be He, connects the idea of prayer with the idea of freewill offerings, for both of them serve as a means of achieving this objective. Regarding the first verse dealing with the sacrifices—"When any of you presents an offering to the Lord" (Lev. 1:2)—commentators have said:[1] "Why is it called korban, an offering? Because the person brings his soul close (mekarev) before his Maker," and Rashi remarks here that this refers to freewill offerings.
[1] Yalkut Teimani, a midrash in: Mehkarim be-Yahadut Teiman, 1999.