“And [the Kohain] shall remove its crop with its feathers and toss it next to the altar on the eastern side, to the place of the ashes” (Vayikra 1:16). On one hand, mentioning “the place of the ashes” seems to indicate that the location where the ashes were put (referring to the ashes from the “t’rumas ha’deshen,” see Rashi) was already discussed, and therefore already known. On the other hand, if it was already known, there should be no reason to specify that this place is “on the eastern side” of the altar. However, in the instructions for removing the ashes every morning (6:3), although we are told that the Kohain should put them “next to the altar,” we are not told on what side of the altar to place them. Why is this detail taught here, where the “t’rumas ha’deshen” is not the focus, rather than later, where it is? [It’s possible that it’s given here because the ashes being put on the eastern side is more closely connected to the crop/feathers than to ashes. Nevertheless, that it is given here and not where the “t’rumas ha’deshen” is taught is certainly noteworthy.]
Another issue with this verse’s wording is raised by Rabbi Isaac S.D. Sassoon (“Destination Torah”); how can the context here indicate that we already know about the requirement to remove some of the ashes every morning (using the location where the ashes are put as a reference point) if that requirement isn’t taught for another five chapters? A similar issue arises a few chapters later (4:12), when the location where the bulk of the ashes are brought (when the pile of ashes on top of the altar gets too big) is used as a reference even though it isn’t taught until a couple of chapters later either (6:4). Rabbi Sassoon attributes the locations of the ashes being used as reference points before they are taught in the text to the concept of the Torah being presented, at times, out of chronological order (see Rashi on Sh’mos 31:18), something that is universally agreed upon (see Bamidbar 1:1 and 9:1), although not always applied universally (see Ramban on Sh’mos 35:1 and Bamidbar 16:1). Rabbi Sassoon seems to present it as if this issue alone is enough of a reason to apply it here; let’s take a closer look to see if this is really the case.
There is a well known dispute (Soteh 37b) about whether Moshe was taught every detail at Sinai, and later repeated in the Mishkan, or if only the categories were taught at Sinai, with the details being taught in the Mishkan. It would be fair to assume that if not every detail was taught at Sinai, where the ashes are to be put was not taught there. However, if every detail was taught at Sinai, and then repeated in the Mishkan (at which point Moshe shared it with everyone else), even if Sefer Vayikra was taught in chronological order, referencing something that does not appear until later would not be as much of an issue, as Moshe already knew it from Sinai. Nevertheless, since it was at this point that Moshe was told to share it with others (in this case, with Aharon and his sons), unless Moshe was supposed to digress from the commandment at hand to elaborate on the “t’rumas ha’deshen,” using it as a reference point wouldn’t work. As far as mentioning which side of the altar the crop/feathers are to be thrown, though, if Aharon and his sons were not yet taught where the ashes should be put, it makes sense for it to be taught here.
That things are taught out of order chronologically in Sefer Vayikra is widely accepted (see Rashi on 8:2, although Ramban disagrees). It opens with G-d calling to Moshe from the Mishkan, which is continuation of how Sefer Sh’mos ended, with the Mishkan fully built, G-d’s presence having descended upon it, and Moshe unable to enter the Mishkan because G-d’s presence had filled it. Since G-d’s presence didn’t descend upon the Mishkan until the “eighth day” (Vayikra 9:1-24), which was preceded by the instructions to Aharon telling him what needed to be done in order for G-d’s presence to descend (8:1-36), obviously the beginning of Sefer Vayikra, where G-d’s presence had already descended onto the Mishkan, occurred after the instructions were given (and performed) in order for it to descend. The question is where this chronological switch, from things taught in the Mishkan to things taught before the Mishkan was fully operational, took place (see
https://rabbidmk.wordpress.com/2012/03/15/parashas-vayakhel-pekuday-5772/). If the switch occurred after chapter 5 ends, with chapter 6 reverting to the earlier time, then the locations where the ashes were put, which are given in chapter 6, were in fact taught before they were referenced in chapters 1 and 4.
There are several indications that this is where this switch occurred, as some of the commandments included in chapters 6 and 7 (6:12-6:16 and 7:35-36) specifically address what Aharon and his sons must do before they start performing the service, i.e. during their seven-day training period (the seven days of “milu’im”), which was obviously before the “eighth day.” These chapters contain the instructions that teach the Kohanim how to bring each type of offering, instructions they needed to learn during their seven day training period. (Every “dibur” in these two chapters, except the last one, is directed to the Kohanim because it contains their instructions.) Additionally, this two-chapter section concludes by telling us that these instructions were given at Sinai (as opposed to the Mishkan), which is where G-d communicated with Moshe before His presences descended upon the Mishkan. Therefore, rather than the mentions of the locations of the ashes being the main reason for placing chapters 6 and 7 before chapters 1-5 (chronologically), the context of the chapters themselves do so. And once chapter 6 occurred before chapters 1 and 4, there is no issue with the locations of the ashes being used a reference point. However, it makes the question of why the ashes being placed on the eastern side of the altar was taught in chapter 1 rather than chapter 6 stronger, as not only is chapter 6 the more appropriate context, but it was taught first too! Why wait until after the seven day training period was over to tell us exactly where these ashes should go?
[There is another issue with chapters 6 and 7 being taught earlier (chronologically) than chapters 1-5; two of the offerings are referenced in chapter 6 as if we already know about them, and if chapters 1-5 were taught afterwards, how would we? However, these references aren’t really problematic. Even though the verse (6:2) indicates that we already know about burnt offerings, this knowledge could have come from the earlier instructions for these offerings brought during the “milu’im” (Sh’mos 29:38-42), and therefore do not need to come from the details taught at the beginning of Sefer Vayikra. The reference to the “sh’lamim” in 6:5 isn’t problematic either, even though this type of offering isn’t introduced until later (7:11), as this offering was brought even before the Mishkan was commanded (see Sh’mos 24:5). All this verse is telling us is that the fats of any “sh’lamim” brought must be put on the altar after the daily morning burnt offering; the fact that the details regarding a “sh’lamim” aren’t taught until later doesn’t prevent an already-known category from being mentioned.]
The Yerushalmi (Yoma 2:2) says our verse (Vayikra 1:16) teaches us that not only are ashes from the outer altar placed on the eastern side of the (outer) altar, but so are the ashes from the inner altar and the Menorah. The words “to the place of the ashes” are otherwise unnecessary, as once we are told that the crop/feathers are to be thrown “next to the altar on the eastern side,” and that the ashes are also put in an area described as “next to the altar” (6:3), we automatically know that the ashes are put on the eastern side of the altar. Therefore, the “ashes” mentioned in 1:16 must be referring to different ashes, i.e. those of the inner altar and the Menorah. (See M’ilah 12a, where the “ashes” in 1:16 are also said to refer to the ashes of the inner altar and of the Menorah, even if something else is learned from these words.) Although on a p’shat level the “ashes” mentioned in 1:16 are from the “t’rumas ha’deshen” (thereby indicating that this commandment was already known), since on a “d’rash” level we are being taught about other ashes, and being told (separately) that the ashes are to be put on the eastern side of the altar contributes to the “d’rasha,” this detail is taught here rather than with the (earlier) commandment about the “t’rumas ha’deshen.” True, had the instructions for them to be on the eastern side been taught there, the words “next to the altar” alone should make the words “to the place of the ashes” superfluous. Nevertheless, having both locators (“on the eastern side of the altar” and “to the place of the ashes”) together makes it more obvious that other ashes are being hinted to here.
This still leaves us with one issue; if 6:3 was taught before 1:16, how did they know which side of the altar to put the ashes from the “t’rumas ha’deshen” on during the seven days of “milu’im” (which were before 1:16 was taught)? Well, since Moshe was the acting Kohain Gadol during these seven days (Vayikra Rabbah 11:6, with Aharon taking over on the “eighth day”), and he knew which side to put the ashes on, Aharon and his sons were able to observe him doing so and could follow his lead. Therefore, there was no reason for Moshe, when he gave over the instructions for the seven days of “milu’im,” to tell them explicitly which side to put the ashes on. And when he gave over the instructions on the “eighth day,” which included which side to throw the crop/feathers, referencing that it is the same side the ashes from the “t’rumas ha’deshen” were put taught them that it must always be on that side.