Yevamot, Chapter Twelve, Mishnah Two
This mishnah relates laws concerning the shoe with which halitzah must be performed.
1) If the woman performed the halitzah with a sandal that did not belong to him, or with a wooden sandal, or with the one of the left foot [which he was wearing] on his right foot, the halitzah is valid.
2) If she performed the halizah with a sandal too large [for him], in which, however, he is able to walk, or with one too small which, however, covers the greater part of his foot, her halizah is valid.
3) If she performed the halitzah at night, her halitzah is valid.
a) Rabbi Elazar disqualifies [halitzah at night].
4) [If she performed it] with [the yavams] left shoe, her halitzah is invalid,
a) Rabbi Elazar validates it.
Section one: Deut. 25:9 says she shall pull off his sandal. From here we might have concluded that if the yavam did not own the sandal, the halitzah was invalid. Our mishnah teaches us that if the halitzah was performed with someone elses shoe that the yavam was wearing it is still valid.
Wooden sandals, although not the normal style of sandal, are nevertheless valid for halitzah, although not preferable.
As long as the yavam wears the shoe on his right foot the halitzah is valid, even if it is his left shoe.
Section two: The sandal which is used for halitzah should fit his foot. However, if it is too large or too small the halitzah is valid, provided he can use it as a sandal. This means that if it is too big he must be able to walk in it, and if it is too small, it must at least cover most of his foot.
Section three: In the previous mishnah we learned that halitzah is considered a court matter and therefore requires three judges. Monetary cases may be completed at night but must be begun during the day. Halitzah is somewhat of a monetary case, because after halitzah she collects her ketubah. The first opinion considers halitzah to be like the last stage of a trial and therefore it may take place at night, whereas according to R. Elazar it is like the last stage of a trial and therefore, must take place during the day.
Section four: According to the first opinion in the mishnah, halitzah must be performed with the shoe from the right foot, whereas R. Elazar holds that it may be also from the left foot.