Yevamot, Chapter Twelve, Mishnah Three
There are three acts in the halitzah ceremony: 1) the womans removal of the yavams shoe; 2) her spitting in front of him; 3) her recitation of the verses in Deuteronomy. Mishnah six below will deal with the recitations stated during the process of halitzah. Our mishnah deals with which acts are essential to a valid performance of halitzah.
1) If she took off his shoe and spat, but did not recite [the formula], her halitzah is valid.
2) If she recited [the formula] and spat, but did not draw off the shoe, her halitzah is invalid.
3) If she drew off the shoe and recited [the formula] but did not spit: R. Eliezer says her halitzah is invalid; and R. Akiva says: her halitzah is valid.
a) R. Eliezer said to him: So shall be done (Deut. 25:9), anything which is a deed is essential.
b) R. Akiva said to him: From there is your proof!: So shall be done to the man, only that which is to be done to the man [is essential].
Section one: Although the recitation of the formula is required, if she does not do it, her halitzah is still valid. This is because all tannaim agree that words are not a deed and only deeds are absolutely essential to the performance of halitzah.
Section two: Drawing off the shoe is the most essential part of halitzah, without which the halitzah cannot be valid.
Section three: This section contains a debate over whether or not spitting is essential to the halitzah. According to R. Eliezer, since spitting is a deed, it is essential. This is derived from the words, so shall be done which are understood to mean that anything that is done is essential to the halitzah. R. Akiva rejects this proof by creatively reading the phrase so shall be done to the man. R. Akiva interprets this to mean anything done literally to the mans body. Spitting is done to the man but not to his body, for according to rabbinic interpretation, she spits in front of him and not in his face as the verse implies.