How does נעלו exclude a סנדל מסוליים?

Question

The Bavli, Y'vamos 103 amud 2, quotes a b'raysa:

[The verse says that, for chalitza, the woman removes] "his shoe". I'd think it must be his own shoe; how do I know it can be anyone's shoe? [The verse also says] "the shoe" [meaning] in any event. If so, what does it mean by "his shoe"? A shoe befitting him: excluding one so large he can't walk in it, excluding one so small it doesn't cover most of his foot, and excluding a m'soliyim sandal that has no heel.

The m'soliyim sandal is named after where it was used, or after the fact that it has no heel. In any event, how does the word "his" exclude a m'soliyim sandal? What is less his about such a sandal than about any other sandal or shoe?

Answer 1

Rashi explains, it's without sole, and since

אנעלו הראוי לו פרט לגדול שאין יכול להלוך בו

the verse excludes a sandal that he cannot walk with it, sandal mesula isn't called Naalo.

From Naalo we learn that the shoe must to be adapted to his needs, by dimensions and by efficacy. A shoe for him, for his needs. Because the Vav doesn't addresses possession as we see from the drasha naal mikol makom.

תנו רבנן נעלו אין לי אלא נעלו נעל של כל אדם מנין ת"ל נעל נעל מכל מקום א"כ מה ת"ל נעלו(רש''י חלוץ הנעל) ‏

Naalo cannot be a drasha regarding ownership, so the Berayta in second choice understands it a adapted shoe, this includes dimensions and efficacy.

Machloket Rashi and Rabenu Tam, according to Rashi, on which your question is based, סוליא. is sole (old French is similar to Italian, in Italian the world is suola, the English word sole is almost the same). The question is based on the pshat of Rashi. The pshat of Rabenu Tam (see Ritba and Tosfot) is that it's heel (talon in French).

Anyway the explanation of "לו" is the same for the two pshats.

Answer 2

Your question stems from misunderstanding the word עקב, which is not heel but the [outside] [counter]1, and that's clear by the Tosfos in place:

המסוליים - שם סנדל אחד כן דאמר בירושלמי ר' יהושע בן לוי נפק בסולייא בלילי צומא רבה ואמרינן נמי (מדרש רבה ש"ה) מה שעשתה חכמה עטרה לראשה עשתה ענוה עקב לסולייתא

עקב לסולייתא meaning "surrounding the outsole" like עטרה surrounding one's head, not our heel, as translated.

The purpose of the counter is to limit the shoe and to fit it to the owner, unlike "סנדל מסוליים" which only has "one size" outsole that's tied to the foot with laces (maybe like flip-flops).

So a shoe that doesn't have that counter, does not fit to his owner and can't be called "his shoe".

Also see the definition of עקב in Hebrew here:

or the original Even Shushan: