Gemara

(Mishnah): If she took off his shoe and spat, but did not recite the verses, the Chalitzah is valid.

If the Yavam or Yevamah was a Cheresh (deaf-mute), or he was a minor, the Chalitzah is Pasul;

(Gemara - Version #1 - Rava): Since reciting the verses is not Me'akev, even if he or she is mute, the Chalitzah is Pasul.

Question (Mishnah): If he or she was a Cheresh, or he was a minor, the Chalitzah is Pasul.

Suggestion: It is Pasul because they cannot recite the verses.

Answer: No, it is because they lack understanding.

Question: If so, the same should apply if he or she is mute!

Answer (Rava): A mute person has knowledge, just his mouth cannot speak.

Objection: D'Vei R. Yanai taught that (when he or she is a Cheresh) it is Pasul because he or she cannot recite the verses!

Retraction: Rather, we must say that Rava taught about the Seifa.

Version #2 (Seifa): If he or she was a Cheresh, or he was a minor, the Chalitzah is Pasul.

(Rava): Since reciting the verses is Me'akev, if he or she is mute, the Chalitzah is Pasul.

The Mishnah says that reciting is not Me'akev (if he and she can speak). This is like R. Zeira taught:

(R. Zeira): If a Minchah is small enough to be mixed, it is valid even if it was not mixed. If it is too big to be mixed (one Log of oil cannot be mixed with more than 60 Esronim of flour. Alternatively, the Keli is too small) it is invalid because it was not mixed.

105a (Mishnah): If he was deaf (or a minor, or she was deaf, the Chalitzah is Pasul).

(Rav Yehudah): This is like R. Meir, but Chachamim say that the Chalitzah of a Katan has no effect.

Gitin 24b (Shmuel): Wherever Chachamim called a Chalitzah 'Pasul', it does not permit her to marry (a stranger), but it forbids doing Yibum;

(R. Elazar): Chalitzah done with the left foot or at night does not permit her to marry, but it disqualifies her from doing Yibum. Chalitzah of a minor Yavam or with a sock does not permit her to marry, nor does it forbid doing Yibum.

Rishonim

Rif and Rosh (12:13): When he or she is a Cheresh it is invalid because he or she cannot recite the verses. The Mishnah is Machshir if she did not recite the verses. This is when she can speak. This is like R. Zeira taught, that mixing a Minchah is Me'akev only if it is too big to be mixed.

Rambam (Hilchos Yibum 4:12): If she did Chalitzah but did not recite the verses it is Kosher.

Rambam (13): This is when they can speak and are able to recite the verses. If one of them is mute they cannot do Chalitzah. If they did, it is Pasul. This is unlike Chalitzah of a Cheresh or Chereshes, which is totally void (it does not forbid Yibum), since they have no Da'as (understanding).

Magid Mishneh: The Rambam learned from a Tosefta (11:9). It says that if (a Yevamah married l'Shuk after Chalitzah in which) he or she was a Cheresh or lunatic, or he was a minor, she must leave him and all 13 fines (for a woman who remarried after one witness falsely testified that her husband died) apply. We equate a Cheresh to a minor for Chalitzah and everything that requires Da'as.

Gra (EH 169:128): In the Tosefta, R. Akiva says that the child is a Mamzer. This shows that the Chalitzah was totally void. Also, Chachamim agree that she must leave her husband. When Chalitzah is Pasul, she may stay!

Question (against Magid Mishneh - Lechem Mishneh): If so, we should also equate Chalitzah of a Chereshes to that of a Ketanah! The Rambam (Halachah 16) says that the latter is Pasul!

Answer (Beis Shmuel EH 169:49): The Rambam discusses a Ketanah who has Da'as. Mid'Rabanan we equate the Yevamah to the Yavam, and disqualify a minor.

Question (against Rambam): The Mishnah says that Chalitzah of a Cheresh or Chereshes is Pasul. Rav Yehudah said that this is like R. Meir, but Chachamim say that Chalitzah of a minor is totally void. Chachamim say so only about a minor, but not about a Cheresh or Chereshes! Also, the Gemara does not disqualify Chalitzah of a Cheresh or Chereshes because they lack understanding, rather, because they cannot speak, due to R. Zeira's law. The same applies to a mute!

Answer #1 (Magid Mishneh): We say that Chalitzah of a Cheresh is Pasul because he cannot speak. This teaches about a mute, but they are not the same (a Cheresh has a more serious Pesul). Rav Yehudah discussed only a minor, because the Mishnah called the Chalitzah 'Pasul' due to the case of a minor. Had it taught only about Chereshim, it would have said that the Chalitzah is totally void. Alternatively, Rav Yehudah taught only what he heard about, i.e. a minor. We learn about Chereshim from the Tosefta. The Ramban and Rashba equate a Cheresh to a mute for Chalitzah. It seems that the Rif agrees with them.

Answer #2 (Shirei Korban on Yerushalmi 12:4 (68a) DH ha'Cheresh): Chalitzah requires Da'as, and the ability to recite. If one lacks one of these, his Chalitzah is Pasul. A Cheresh lacks both of these, therefore his Chalitzah is totally void.

Answer #3 (Keren Orah 104b:DH Omar): The Ramban explains that the Mishnah discusses deaf people who can speak. They have Da'as. The only problem is the recital.

R. Akiva Eiger (EH 169:6): Since they cannot hear each other, the recital does not help.

Answer #4 (Beis Meir EH 169:43): A Cheresh can divorce only if he or she was a Cheresh from the time of Kidushin. Then since the Kidushin was without Da'as (it is only mid'Rabanan), he can divorce. Likewise, if the Mes was a Cheresh, we are not concerned if also the Yavam lacks Da'as. Rav Yehudah and our Mishnah did not say that Chalitzah of a Cheresh is totally void, for they discuss when the Mes was a Cheresh. The Chalitzah is Pasul only because he cannot speak. However, the Rambam did not specify that in this case the Chalitzah is Pasul.

Answer #5 (Aruch l'Ner b'Tosfos DH v'Ha): The Mishnah says that Chalitzah of a Cheresh is Pasul. A Beraisa says that it is totally void. The Rambam explains that it is Pasul when Beis Din instructs the Cheresh. If not, it is void.

Answer #6 (Beis ha'Levi 3:2:1): Rav Yehudah holds that 'Chalitzah Pesulah' always forbids Yibum. R. Elazar establishes our Mishnah like Chachamim. He holds that it is Pasul and void. The Rambam rules like R. Elazar.

Poskim

Shulchan Aruch (EH 169:43): If she did Chalitzah but did not recite the verses, it is Kosher. This is when they can speak and are able to recite the verses. If one of them is mute or she is a minor they cannot do Chalitzah. If they did, it is Pasul. This is unlike Chalitzah of a lunatic or Katan, which is totally void and does not forbid Yibum. Some say that Chalitzah of a Cheresh or Chereshes is totally void.

Gra (EH 169:129): This is the Rambam's opinion. It is astounding.

Shulchan Aruch (ibid.): Some say that it is Pasul, like that of a mute.

Beis Shmuel (44): Tosfos (104b DH v'Ha) says that we do not totally void Chalitzah of a Cheresh or Chereshes due to their lack of Da'as, because Beis Din instructs them. This is why they can write a Get. Therefore, the Chalitzah is Pasul only because they cannot speak, just like mutes.