The general principle that the Gemara works with is that kohanim zerizin hem – that kohanim in the Temple are always careful and efficient in their work. Nevertheless, the Mishna (53b) presents the position of Rabbi Yehuda that there was only one stand upon which the blood could be put down, because were there to be two stands, one for the blood of the par (bull) and one for the blood of the se’ir (goat) it would be possible to mistake one for the other, and the wrong blood may be sprinkled.
But in that case, let us place two pedestals and write on them which one is for the bull and which is for the goat. Rather, it is clear that Rabbi Yehuda does not accept that one may rely on writing in a situation where error is possible.
One place where clear designations were accepted in the mikdash was the shofarot – collection boxes for a variety of sacred purposes.
Money was collected for use in the Bet ha-Mikdash in different ways. There were actually 13 collection boxes, which were called shofarot because they were shaped like a shofar – a ram’s horn – with one end small enough for a coin to be placed into it and a larger end where the coins could be removed. (They were made in this way so that no one who came to deposit money would be suspected of stealing.) Each shofar was marked with the purpose of its money, so that no mistakes would be made. For example, one said “new shekalim” for the monies that were deposited for the fiscal year beginning in Nisan, one was marked “old shekalim” for the leftover monies from last year’s collection, etc.
The Me’iri points out that the money collected in these shofarot was only for general communal sacrifices. Other sacrifices, which needed to be “personalized” by having the owner place his hands on the animal prior to the sacrifice (semikha) could not be collected here, since the owner needed to accompany the animal that was purchased with his money. There are a number of other sacrifices that did not have shofarot because they were brought only occasionally, and only common sacrifices had collection boxes in the Temple.
Based on the ruling regarding the shofarot, the Gemara concludes that even Rabbi Yehuda will have to admit that if the stands were clearly marked it should keep the kohen gadol from making an error. The conclusion of the Gemara is that Rabbi Yehuda fears that due to his weakness, the fasting kohen gadol may make mistakes that he would not have made otherwise.