Menachos, Chapter 4, Mishnah 1. At the end of the previous chapter we learned about mitzvos that have several components which depend on one another: there is no point in shaking a lulav without an esrog, since all four species are required, and likewise there is no benefit in attaching tzitzis to three of the garment's four corners, rather they must be placed on all of them. Now the Mishnah turns to mitzvos that have several components, but where each component stands on its own as an independent mitzvah.
The Mitzvos of Techeiles and Lavan:
The first topic in the Mishnah is techeiles - the woolen threads dyed blue with a dye produced from the chilazon. The chilazon was a sea creature, and many hold that it was a sea snail known as the Murex trunculus. Either way, the point is that there is a mitzvah to have blue threads in the tzitzis on the garment, in addition to the mitzvah of tzitzis itself fulfilled through the threads themselves.
The Mishnah calls the remaining threads "lavan," and the intent is not specifically the color white, but rather in contrast to techeiles - the threads dyed blue. And so we learned: "HaTecheiles einah me'akeves es haLavan, v'haLavan eino me'akev es haTecheiles" - the techeiles does not hold back the lavan, and the lavan does not hold back the techeiles. If a person has only techeiles threads, he has fulfilled the mitzvah; and if he has only white threads, as many do today without techeiles, that too is valid. Each one is a mitzvah in its own right, and the absence of techeiles does not detract from the completeness of the mitzvah of tzitzis. The mitzvah of tzitzis is complete, and techeiles is an additional mitzvah.
How is the mitzvah of techeiles fulfilled in practice? The Rishonim disagree about this, regarding the four threads that are folded over the corner and form eight ends:
Rashi, Tosafos and most of the Rishonim: two threads of techeiles and two white threads, and once they are folded in half, four blue and four white.
The Raavad, and the Vilna Gaon inclines this way as well: one of the four threads is techeiles, and once they are folded, two out of the eight are the color of techeiles.
The Rema: three white threads, and the fourth is half white and half techeiles, and once they are folded, one end of techeiles and seven white.
In any case, from the seventh or eighth century, after the Islamic conquest of Eretz Yisrael, the Muslims did not attribute cultural importance to blue as a dye color, and the tradition of preparing techeiles was lost long ago. Whether it has returned in our times or not is a question in its own right. In any event, the first part of the Mishnah is straightforward: the two mitzvos stand independently, and even one whose tzitzis have no techeiles fulfills the mitzvah of tzitzis.
The Mitzvah of Tefillin:
"Tefillin" is a plural word, referring to two separate boxes, and its singular form is "tefillah" - the same form as the word tefillah, prayer, in Hebrew. One is placed on the arm, the shel yad, and one on the head, the shel rosh, and the two are two separate mitzvos. In fact, the shel yad and the shel rosh are counted as two of the 613 mitzvos, just as techeiles and tzitzis are counted as two mitzvos.
Therefore we learned: "Tefillah shel yad einah me'akeves shel rosh, v'shel rosh einah me'akeves shel yad" - the tefillah of the arm does not hold back that of the head, and that of the head does not hold back that of the arm. One who has only tefillin shel yad and does not have a shel rosh should put on the shel yad. And if he cannot put on the shel yad, whether because his arm is broken, or because the tefillin were damaged, or because he has no arm, he should put on the shel rosh by itself. These are two independent mitzvos, and whichever one can be fulfilled should be fulfilled.
The Fine Flour, the Oil and the Wine:
From here the Mishnah returns to the subject of the offerings. In the nesachim - those agricultural components that accompany every olah and every shelamim - there are two elements: the minchah, which is made up of fine flour and oil, and the wine. The fine flour and the oil hold each other back, and a minchah may not be brought without both of its components; however, the minchah and the wine are not dependent on one another.
And so we learned: "HaSoles v'haShemen einan me'akvin es haYayin, v'lo haYayin me'akvan" - the fine flour and the oil do not hold up the wine, nor does the wine hold them up. If one has fine flour and oil but no wine, he brings the minchah; and if he has wine but not the ingredients of the minchah, he brings the wine. The absence of the flour or the oil does not nullify the pouring of the wine, and the absence of the wine does not nullify the bringing of the minchah made of fine flour and oil.
The gifts of blood:
Let us recall what we learned in Maseches Zevachim, that the last of the four blood services is the zerikah - the placing of the blood. The technical name for those bloods that are placed is "matanos," that is, gifts in the literal sense of the word. And in most offerings there is more than one gift:
Two that are four: two throws at the northeast and southwest corners, which are considered as four because the blood reaches all four walls. This is the case with the olah, the asham, the shelamim and the todah.
Four gifts: with the chatas the blood is placed four times, on the four corners of the altar.
The novelty of our Mishnah is that once a single throw has been performed and one gift has been placed, the owner of the offering has already fulfilled his obligation, and one gift does not hold up the other. Even if he missed the northeast corner, whether because he was not paying attention or because he did not do it at all, and he placed the blood with the second throw at the southwest corner, he has fulfilled his obligation after the fact.
And this is the language of the Mishnah: "HaMatanos she'al Mizbe'ach haChitzon, ein hen me'akvos zo es zo" - the gifts of blood placed on the outer altar do not hold one another up. This is in contrast to the inner altar, which we discussed at the end of the previous chapter. There, with the five inner sin offerings, every single gift is indispensable, meaning each and every side; whereas on the outer altar one gift suffices in all the offerings. Each one is not dependent on the other, and as long as one gift of blood has been placed, the offering has fulfilled its function, its owners receive atonement, and there is no need to bring a new offering.