There are olive trees within the precincts of the mosque, and my father covers the costs of electricity, water, and other needs of the mosque. Is it permissible for him to take the olive harvest?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
If trees and fruit-bearing crops are planted in a mosque for the mosque itself, they may only be spent on the mosque’s interests. If they were planted for the public way (musabbalah), that is, for the general public, then any Muslim who enters the mosque may eat from them. If the planter’s intention is unknown, they are treated like those dedicated for public use, wherever custom has so run.
It is stated in Tuḥfat al-Muḥtāj (Vol.6/p.295): “The fruit of a tree planted for the mosque within it is not freely permitted without compensation. Rather, the imam spends its equivalent value on the mosque’s interests. The tree left its planter’s ownership here without any verbal declaration because of the evident indication. The case of planting it for the mosque excludes planting it as musabbalah, in which case eating from it without compensation is permissible, and likewise if his intention is unknown, where custom has so run. The tree may be uprooted from the mosque if the imam sees fit. Indeed, if he makes the plot a mosque while a tree stands in it, the imam may uproot it, even if the endower included it within the endowment (waqf).”
The father is a donor (mutabarriʿ), so he is not entitled to take anything in return for his donation to the mosque.
The Ministry of Awqāf is the body that supervises the affairs of endowments, so it must be consulted and the Sharīʿah and administrative instructions regulating such matters must be considered. And Allah Almighty knows best.
Does the clipping of nails nullify ablution?
No, it does not, and it is preferable to wash the hands afterwards.
I bought an apartment, and I am saving money to pay the remaining balance of its price — is zakāh obligatory on this money?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
Zakāh is obligatory on all saved/hoarded wealth. Once the total wealth reaches the niṣāb (minimum threshold liable for zakah— equivalent to the value of 85 grams of pure 24-karat gold) and a full ḥawl (lunar year) has elapsed over it, zakāh becomes obligatory at a rate of (2.5%) — even if the wealth is earmarked for basic future needs, and even if the wealth's owner is in debt. Debt does not prevent the obligation of zakāh, nor is it deducted when calculating the zakāh due, based on the general and unrestricted wording of all the Qur'anic verses commanding zakāh, which draw no distinction between someone in debt and anyone else.
It is stated in ‘Umdat as-Sālik, from the books of the Shāfi‘ī school: "If someone possesses exactly the niṣāb, and owes an equivalent amount in debt, zakāh remains obligatory on what is in his possession, and the debt does not prevent this obligation" — meaning, the obligation of zakāh on what is presently in his possession.
The ḥawl (annual cycle) recognized for zakāh, as well as for the other sharī‘ah obligations that Allah, the Exalted, has imposed upon Muslims, is the Hijrī (lunar) year. And Allah, the Exalted, knows best.
What are the categories of the livestock permissible for Udhiyah?
In the Name of Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
An Udhiyah (sacrificial offering) is only valid if it is selected from Al-An'am (livestock), which includes: camels, cattle, and sheep or goats—whether male or female, and even if castrated. Allah Almighty says {what means}: "And for all religion We have appointed a rite [of sacrifice] that they may mention the name of Allah over what He has provided for them of [sacrificial] livestock." (Al-Hajj/ 34)
In terms of preference, camels are considered the best choice, followed by cattle, then sheep, and finally goats.
A single sheep or goat is valid as a sacrifice on behalf of one person. However, a single camel or cow can be shared by up to seven people. This is based on the narration of Jabir (may Allah be pleased with him), who said: "In the year of Al-Hudaybiyah, we sacrificed along with the Messenger of Allah (peace and blessings be upon him) a camel on behalf of seven people, and a cow on behalf of seven people." (Narrated by Muslim)
(Note: The term "Badanah" used in the original Arabic text specifically refers to a camel in this context). And Allah the Almighty Knows Best.