What is incumbent upon the one offering the sacrifice if, after slaughtering the animal, they discover that one of its internal organs is damaged or diseased?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
The presence of disease or defect in the internal organs of a sheep does not affect the validity of the sacrificial animal, unless the disease leads to the animal becoming emaciated and its meat becoming corrupted.
It is stated in al-Iqnā' (2/590) by Imam al-Shirbīnī: "The third disqualifying condition: an animal with a manifest illness — meaning one whose illness visibly results in emaciation and corruption of its meat. However, if the illness is minor and does not produce such effects, it doesn`t affect the validity of the sacrificed animal." And Allah Almighty knows best.
When is it Sunnah 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 on the seventh day from the birth of the newborn. According to the sounder position, the day of birth itself is counted as the first of the seven days. Thus, for example, if the child is born on a Saturday, the 'aqīqah is to be slaughtered on the following Friday. If the child is born at night, the count begins from the day that follows. And Allah Almighty knows best.
What is the ruling on offering a sheep as a sacrifice (Udhiyah) if its fat-tail is sound, except that when it was young, the tip of its fat-tail was cut so that it would grow larger? And what is the ruling in case of doubt regarding the amount that was cut?
In the Name of Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
Cutting a minor, insignificant portion from the tip of an animal's fat-tail (al-alyah) to encourage it to grow larger is not considered a defect, and it does not prevent the animal from being valid for sacrifice (Udhiyah).
It is stated in Tuhfat al-Muhtaj (Vol.9/P.352): "There is some scholarly deliberation regarding the common practice of cutting the tip of the fat-tail so that it grows larger. It could potentially be likened to a partial cut of the ear—supported by the jurists' general rule: 'even if it is a small amount.' On the other hand, if it is an exceptionally minor cut, it might have no effect on validity. This is explicitly clarified by the juristic exception to the general rule, which states that cutting a tiny piece from a large limb causes no harm. This latter view is more well-founded.
Furthermore, I found that some scholars investigated this matter and concluded: 'It should not affect validity if a custom-sanctioned portion of its fat-tail is removed during its youth to make it grow larger and look better, just as castrating a male animal causes no harm.' However, applying this unconditionally contradicts the established texts of the jurists, as understood from what I have laid out; thus, the restriction I specified is what must be relied upon."
Similarly, it is mentioned in Nihayat al-Muhtaj (8/135): "If a small piece is cut from the fat-tail to help it grow larger, the most well-founded view is that the sacrifice remains valid, as was given in a formal legal verdict (Fatwa) by my father [Shihab al-Din al-Ramli], may Allah be pleased with him. This is proven by the jurists' maxim: 'The loss of a tiny piece from a large limb causes no harm.'"
In cases where there is doubt as to whether the portion cut was large or small, the animal is still deemed valid for sacrifice. It is noted in Hashiyat al-Shubramallisi ‘ala Nihayat al-Muhtaj (Vol.8/P.135):
"This matter requires careful consideration, but the closer and more correct view is that it is valid. This is because soundness is the default state for the animal from which the piece was cut, and it aligns with what usually occurs—namely, that the part removed to help the fat-tail grow larger is naturally very small." And Allah the Almighty Knows Best.
When does the time for the 'aqīqah lapse and pass?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
If the guardian was financially capable (mūsir) during the majority of the postnatal period (nifās) — which is sixty days — then the obligation of the 'aqīqah remains upon him until the child reaches the age of maturity (bulūgh). Once the child reaches maturity, the demand falls away from the father and those like him. At that point, it becomes Sunnah for the child himself to perform the 'aqīqah on his own behalf.
However, if the guardian was financially incapable (mu'sir) during the postnatal period, and then became financially capable after its expiry — that is, after sixty days — the 'aqīqah is no longer required of him. And Allah Almighty knows best.