Is the son of the sister by breastfeeding considered a mahram in Islam, and is it permissible for a woman to go for Hajj with him?
Everything that is prohibited by lineage is also prohibited by breastfeeding. The son of the sister by breastfeeding is considered a mahram, just like the son of the sister by blood, and it is permissible for him to be her mahram for Hajj and Umrah. And Allah Knows Best.
"If the fidyah becomes obligatory upon a pregnant or nursing woman because she broke her fast out of fear for her child, is it obligatory from her own wealth, or from her husband's wealth?"
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
The fidyah (ransom/compensation payment for breaking the fast) is obligatory from the wife's own wealth, and is not obligatory upon the husband unless he voluntarily chooses to pay it on her behalf.
It is stated in Mughnī al-Muḥtāj (Vol.2/P.174): "If the two [the pregnant woman and the nursing mother] fear for the child alone — such as a pregnant woman fearing miscarriage, or a nursing mother fearing that her milk supply would decrease, thereby endangering the child — then both the qaḍā' (making up the missed fast) and the fidyah become obligatory upon them, to be paid from their own wealth." And Allah, the Exalted, knows best.
What is the ruling on combining more than one intention in the prayer, such as combining the *sunnah* of wuḍūʾ with the pre-Dhuhr *sunnah*, or combining the *sunnah* of greeting the mosque (*taḥiyyat al-masjid*) with the pre-Dhuhr *sunnah*?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
Combining two intentions in a single act of worship, which some jurists call the “overlapping of acts of worship”, has several cases and precise rules. These can be consulted in the books of legal maxims, such as al-Manthūr fī al-Qawāʿid al-Fiqhiyyah by al-Zarkashī and al-Ashbāh wa’l-Naẓāʾir by al-Suyūṭī. Among the most important of these rules:
First: If all of the acts of worship that one wishes to combine under one intention are obligatory, the intentions do not overlap. An example is combining the intention of the obligatory ʿAṣr prayer with that of the obligatory Dhuhr prayer. The intentions do not overlap in this case.
Second: If the two acts are specified supererogatory prayers (nawāfil muqayyadah) that are aimed at in themselves because of a particular time, occasion, or cause, or if they are an obligatory prayer and a specified supererogatory prayer, the intentions again do not overlap. An example is the Duha prayer, which may not be combined with, for instance, the regular sunnah of Dhuhr.
It is stated in Bushrā al-Karīm: “Whatever is not, in meaning, an absolute voluntary prayer, such as the Duha sunnah… is not subsumed under another. Rather, if he intends something else along with it… the prayer is not validly entered. This is because combining two obligations, two specified supererogatory prayers, or an obligation and a specified supererogatory prayer invalidates the prayer in cases not built upon overlapping, as ritual purification (ṭahārah) is.”
Third: If the two acts are absolute voluntary prayers (nawāfil muṭlaqah), or one of them is, where the texts of the Sharīʿah show that the aim of the voluntary act is to fill the time with worship, then overlapping of intentions is permissible. An example is the obligatory Dhuhr prayer together with the sunnah of greeting the mosque (taḥiyyat al-masjid). 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.
