What is the difference between Qiyam al-Layl and Tahajjud?
● Qiyam al-Layl refers to any voluntary prayer performed at night, including Tarawih.
● Tahajjud specifically refers to voluntary prayer performed at night after waking up from sleep.
Glad tidings to those who combine both, as numerous Quranic verses and hadiths mention their virtues.
Allah Almighty says {what means}: "And rise from thy sleep and pray during part of the night [as well], as a free offering from thee, and thy Sustainer may well raise thee to a glorious station [in the life to come." [Al-Isra`/79]
The Prophetﷺ said: "Whoever stands (in prayer) during Ramadan with faith and seeking reward, all their past sins will be forgiven." [Agreed upon]
What is the ruling on performing istinja' with perfumed tissues or a tissue moistened with water?
Performing istinja' with perfumed or moistened tissues is not sufficient if they are not dry, due to the moisture on them reaching the impurity, which increases its spread rather than reducing it. Then, to remove the impurity, one must use pure water. And Allah the Almighty knows best.
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.
Is it valid to perform the obligatory prayer while sitting?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
Standing (Al-Qiyam) while having the ability to do so is one of the pillars (Arkan) of the prayer; the obligatory (Faridah) prayer is not valid without it. However, whoever is unable to stand may pray sitting down. As for voluntary (Nafilah) prayers, it is permissible to pray them sitting even if one is able to stand, but the one sitting receives half the reward of the one who prays standing. And Allah the Exalted knows best.