Is it permissible to offer mandatory prayer while sitting?
All perfect praise be to Allah, The Lord of The Worlds, and may His Peace and Blessings be upon our Prophet Muhammad and upon all of his family and companions. Standing up is a pillar in the mandatory prayer and the prayer is not valid without it unless one cannot do it. As for Nafila (supererogatory prayer), one can perform it in the state of sitting even if he/she can stand, but his/her reward is half the reward of the person who prays while standing if he/sh has no legal excuse for such an act. And Allah Knows Best.
What is the ruling on istibra' and how is it performed?
Istibra' (cleansing from urine) is recommended. It is for a person to ensure that nothing remains of urine in its passage before performing istinja'. Its method is: to clear the throat (or cough slightly), shake the penis (meaning to pass fingers along it to expel any remaining urine if needed), and walk a few steps to the extent that one thinks nothing of urine remains if walking is needed. Each person knows his own nature best. The preferred opinion is that this differs among people. The objective is for one to think that nothing remains in the urinary passage that he fears will exit later. And Allah the Almighty knows best.
Is it permissible to agree with a butcher to purchase the meat of an animal after it has been slaughtered — for instance, by buying the meat of a sheep at a price determined by the weight of its meat following slaughter, at a fixed rate per kilogram? And what is the ruling if the animal is being purchased with the intention of it being an uḍḥiyyah (sacrificial offering)?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
It is not permissible to sell livestock in the manner of pricing each kilogram of meat after slaughter at a fixed rate, because the meat within the animal prior to slaughter is unseen and unknown. This leads to jahālah (ignorance of the subject matter) and gharar (contractual uncertainty), both of which are among the invalidating factors in sales transactions.
However, it is permissible for the buyer to issue a promise to purchase the meat of the animal after slaughter at a specified price per kilogram, with the actual sale being concluded at the time of weighing the meat — at which point both the quantity of the goods and the total price become known. There is no Sharī'ah objection to this arrangement.
The jurists have stipulated that for a sale to be valid, both countervalues must be present and observable. Al-Khaṭīb al-Shirbīnī, may Allah have mercy upon him, states:
"It is valid to sell a heap of grain whose total measure is unknown to both contracting parties at a rate of one sā' per dirham. This sale is valid because the subject of sale is present and observable, and ignorance of the total price is not harmful since it is known in detail — and uncertainty is thereby lifted."— [Mughnī al-Muḥtāj, Vol.2/P.355]
As for the uḍḥiyyah, the 'aqīqah, and vowed blood sacrifices (al-dam al-mandhūr) — full ownership of the animal must be established prior to slaughter. It is not valid for such animals to be slaughtered while still in the ownership of the butcher. Rather, the animal must be purchased alive and then slaughtered with the intention of uḍḥiyyah or the like. And Allah Almighty knows best.
Who is the one required to slaughter the 'aqīqah?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
It is Sunnah for the 'aqīqah to be slaughtered by the guardian of the newborn — the one upon whom the child's financial maintenance is obligatory — provided he is financially capable of doing so. 'Alī ibn Abī Ṭālib, may Allah be pleased with him, reported: "The Messenger of Allah ﷺ performed the 'aqīqah for al-Ḥasan with one sheep." — Narrated by al-Tirmidhī. And Allah Almighty knows best.