Why is a suka forbidden for other uses all the eighth day, but an esrog is permitted after use?

Question

The Talmud Bavli, Suka 46 amud 2, cites a difference of opinion as to how long an esrog and a suka are muktzim l'mitzvosehem, set aside for their respective mitzvos and forbidden for use for other purposes:

R. Yochanan said: An esrog is forbidden for personal benefit on the seventh day [of Sukos–Sh'mini Atzeres] but permitted on the eighth; a suka is forbidden even on the eighth. Resh Lakish said: An esrog is permitted even on the seventh.

Rashi explains that Resh Lakish holds the esrog is permitted for benefit straight after it's been used for its Mitzva.

It's not clear (to me) from the Talmud and Rashi what Resh Lakish holds about suka. However, from the wording quoted above it seems to me that he agrees with R. Yochanan. Moreover, my kid assumed (or learned?) that that's what Resh Lakish holds.

The Talmud continues:

R. Papa said to Abaye: According to R. Yochanan, what's the difference between esrog and suka [that the latter is permitted on the eighth day and the former is not]? He told him: A suka, which is fit for twilight (if he happens to have a meal [then], he must sit in it and eat in it), is muktza for twilight, and because it's muktza for twilight it's muktza for the whole eighth day. An esrog, which is not fit for twilight, is not muktze for twilight, so is not muktze for the whole eighth day.

My kid asked:

According to Resh Lakish, an esrog is forbidden during twilight at the start of the seventh day, yet becomes permitted during the seventh day. Yet a suka is forbidden for use all of the eighth day because it's forbidden during twilight of the eighth day. What's the difference? Why isn't a suka permitted for use after its usage time is done, i.e. after twilight, just as an esrog is permitted for use after its usage time is done?

---

I will be glad to learn that Resh Lakish in fact does not agree with R. Yochanan about suka and holds that it become permitted for use after twilight, assuming that someone finds better evidence for such a claim than the wording of the Talmud quoted above or the existence of this question (or ones like it).

Answer 1

This is a list of things which are Ossur behanaa (forbidden for benefit) for ever. in Talmud-Gemara Avoda zara 74a:

מתני' אלו אסורין ואוסרין בכל שהו יין נסך ועבודת כוכבים ועורות לבובין ושור הנסקל ועגלה ערופה וציפורי מצורע ושער נזיר ופטר חמור ובשר בחלב ושעיר המשתלח וחולין שנשחטו בעזרה הרי אלו אסורין ואוסרין בכל שהוא

Among the list: Eglah Arufa, the hair of a nazir,the bird that was shechted for the metzora and the goat to Azzazel, are all Cheftzei mitzva (articles which have been used to fulfill a mitzva), and they are subsequently forbidden for benefit because of Various pesukim from the torah that indicate so. But these are exceptional. Other Cheftzei Mitzva once fulfilled their Mitzva are not forbidden to benefit from forever Including a Succah, lulav, etrog,shofar.

Succah is only forbidden to have benefit from the wood Min hatorah (because it is dedicated for Hashem) for 7 days as it says in Succah 9a.

אמר רב ששת משום ר"ע במנין לעצי סוכה שאסורין כל שבעה ת"ל חג הסוכות שבעת ימים לה' ותניא רבי יהודה בן בתירה אומר כשם שחל שם שמים על החגיגה כך חל שם שמים על הסוכה שנאמר חג הסוכות שבעת ימים לה'

It is also forbidden Miderabanan on the last days of Yomtov as stated in Shabbos 45a:

תניא סיככה כהלכתה ועיטרה בקרמים ובסדינין המצויירין ותלה בה אגוזין אפרסקין שקדים ורמונין ואפרכלי של ענבים ועטרות של שבולין יינות שמנים וסלתות אסור להסתפק מהן עד מוצאי י"ט האחרון
i.e since the sechach and decorations were mukza bein hashmoshos they are mukza for the last 2 days of yomtov as well, see S.A O.C 638,2.

For an Esrog, there is no specific pasuk to forbid it once used for the Mitzva so Reish lakish says once you fulfilled your last Mitzva on the 7th day, you can eat it as it was only mukza until the Mitzva was completed.

---

{The Halacha follows Rabbi yochanan who argues and says if it was mukza on the 7th day it is mukza for the whole day, but it is still mutar the next day. The reason why it is not forbidden the last 2 days is specified in the Ran(quoted beis yosef OC 665): ליכא למימר דמגו דאתקצאי לבה"ש אתקצאי לכולי יומא משום דלבין השמשות גופיה לא אתקצאי שהרי בין השמשות אינו ראוי למצות אתרוג שאפילו לא נטל כל היום אינו נוטלו בין השמשות דכיון דלולב בזמן הזה מדרבנן בר מיום ראשון ובין השמשות ספק הוא ספיקא דרבנן לקולא - We do not say since that an estrog was mukza bein hashmoshos on the 7th day of succos which would make it subsequently mukza the 8th day, because a person cannot fulfill his mitzva of estrog bein hashmoshos since anyway the 7th day is only Chayav Miderabanan nowadays (only the first day is Chayav deoraisa to shake the lulav and esrog) and Bein hashmoshos is safek 8th day, so Safek derabbanan Lekula and there is no Mitzva to shake the Lulav and etrog after Bein hashmoshos starts).}