The Gemara has been discussing the rules for the preparation of a para aduma – a red heifer – which is burned and its ashes used in the act of purifying someone who has become ritually defiled by coming into contact with a dead body (see Bamidbar 19). Aside from the inherent difficulty that exists in understanding this halakha, our Gemara records that the text of Bamidbar 19 is very difficult to decipher using the ordinary methods used by the Sages.
Rabbi Asi reports in the Gemara that when Rabbi Yohanan and Reish Lakish would study the laws of para aduma, they barely succeeded in coming up with any new insights. The expression that Rabbi Asi used was that they only came up “with the footprints of a fox on a plowed field.” This expression refers to the fact that a fox’s footprints are among the smallest ones found in nature. This is due to the fact that a fox walks on its toes, and since a fox is very light and quick, it barely leaves an impression in the soil.
The difficulty faced by the Sages was that ordinarily a methodology of Midrash can be applied to each parasha in the Torah that allows the Sages to move beyond the simple meaning of the text and derive more halakhot based on this methodology. With regard to para aduma there is no single method that can be applied to the entire parasha, making it very difficult to go beyond the established tradition in interpreting the text.
Nevertheless, the Gemara does present some of the traditional interpretations of the parasha. For example, the parasha commands that the heifer be given to Elazar ha-Kohen. Who will play this role in the future? Can it only be a kohen gadol? Perhaps, as is the case with regard to sacrifices in general, even someone who is not a kohen can be the one who slaughters the animal. These are some of the questions discussed by the Gemara.
The Gemara is certain that participation in preparation of the para aduma is limited to men, and women are excluded. Similarly, a tumtum or androgenus cannot participate. Both of these groups are people whose gender is unclear, the tumtum because we cannot tell whether it is a man or a woman, and the androgenus who shows both male and female sexual organs.