What should a person, who doubts the validity of his Wudu, or over performs it, do?
One who doubts the validity of his/her Wudu while performing it should redo it until he/she is certain of having attained purity. But, if doubt was after having performed Wudu, then he/she should not pay attention to that as doubt after the end of an act of worship does not count. This is of course in case doubt was within the reasonable limits since once it goes beyond that, it becomes a whispering of the Shaytaan (devil) which he/she should ignore as the Wudu is valid.
What is the ruling on one who vows to fast a specific or non-specific year? Are the two Eids, the days of Tashreeq, Ramadan, and the days of menstruation and postnatal bleeding included in them? And do these days break the consecutiveness if it was intended?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
If someone makes a vow (Nadr) to fast a specific, designated year, this vow does not include the days of Eid, the days of Tashreeq (the three days following Eid al-Adha), Ramadan, or the days of menstruation (Hayd) and postnatal bleeding (Nifas). Furthermore, there is no requirement to make up (Qada) these specific days.
However, if someone vows to fast a year that is not specifically designated (i.e., any twelve-month period) and stipulates that the fasting must be consecutive, they are bound by that condition. They must not fast on the days of Eid, during Ramadan, or during menstruation, but they are required to make up these days afterward—with the exception of the days of menstruation and postnatal bleeding, which do not need to be made up.
It is stated in Hashiyat al-Bajuri ‘ala Sharh Ibn Qasim ({Vol.2/P.606): 'If one vows to fast a specific year, the Eid, Tashreeq, Ramadan, and days of menstruation or postnatal bleeding are not included. This is because Ramadan does not accept any fast other than its own, and the others do not accept fasting at all. Therefore, they do not enter into the vow, and no makeup is required for them because they are legally excluded—contrary to Al-Rafi’i regarding menstruation and postnatal bleeding.
If one vows to fast a non-designated year: if they stipulated consecutiveness (Tatuabu’) in their vow, they must fulfill it; otherwise, they are not bound to it. Consecutiveness is not broken by the days that do not enter into the specific year vow (Eid, Tashreeq, Ramadan, menstruation, and postnatal bleeding). However, one must make up the days missed—excluding the time of menstruation and postnatal bleeding—immediately following the end of the year. As for the time of menstruation and postnatal bleeding, it is not made up, contrary to Ibn al-Rif’ah, who argued that it must be made up just like Ramadan.' And Allah the Exalted knows best.
What is the ruling on congregational prayer performed outside the mosque, and is it a condition that it be performed in a mosque in order to attain the full reward?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
It is not a condition for attaining the reward of congregational prayer that it be performed in a mosque; however, a Muslim should still be keen to perform his prayers in the mosque, so as not to miss out on immense reward. This is due to the virtue of the mosque and of spending time there (i‘tikāf), the typically larger number of worshippers present, and the additional reward gained through walking to and from the mosque. On the authority of Abū Hurayrah (raḍiyallāhu ‘anh), the Messenger of Allah ﷺ said: "Whoever purifies himself in his house, then walks to one of the houses of Allah to fulfill one of the obligations Allah has prescribed, one of his steps will erase a sin, and the other will raise him a degree [in status]." (Related by Muslim)
Whoever misses congregational prayer at the mosque should still strive to pray in congregation at his workplace, or together with the members of his household. And Allah, the Exalted, knows best.
What is the Islamic ruling on one who was unable to fast and then regained the ability?
He is not required to make up the fast (Qada) even if he becomes capable of it; whether he regained the ability to fast after paying the fidya (feeding a needy person for each day of missed fasting) or before it, because he was liable for paying it in the first place, so it remains binding upon him. However, if he delayed paying it beyond the first year, nothing is required of him due to the delay. If he is unable to pay it, it does not remain as a debt upon him. And Allah the Exalted knows best.