What is the ruling on the intention of fasting, where is its place, and when is its time?
The intention is a pillar of acts of worship; it is essential, and worship is not valid without it.
Its place is in the heart, and verbalizing it is recommended so that the tongue reminds the heart. Its meaning is to be determined to abstain from nullifiers of fasting during the upcoming day with the intention of worship and obedience to Allah Almighty. This meaning is naturally present in every Muslim on every night of Ramadan, so there is no need for obsessive doubts. If one says, "I intend to fast tomorrow for the sake of Allah," it removes any doubts.
Its time is from after sunset until before the true dawn.
What is the ruling on performing dry ablution (tayammum) on a wall or stone?
One of the conditions for tayammum is that it be with pure, clean dust (soil). It is not valid to perform tayammum by striking stones, a wall, sand that has no dust (i.e., that does not produce dust), pebbles alone, or clay, as these are not from the earth or its same category. And Allah the Almighty knows best.
Is Zakah (obligatory charity) due on the Zakah money received by a poor person, and reached a Nissab (minimum amount liable for Zakah), and a whole lunar year had lapsed over having it in his possession?
Yes, the poor who possessed a Nissab for a whole lunar year is obliged to pay the Zakah due on that money even if it was given to him as a Zakah money in the first place. And Allah Knows Best.
What is the ruling on using the *subḥah* (prayer beads) to count during *tasbīḥ* and *dhikr*?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is recommended to use the ordinary or electronic subḥah (prayer beads or counter) to count tasbīḥ, dhikr, and istighfār, because it helps one to remember Allah. Many reports have been transmitted from the Companions and the Followers (tābiʿūn) showing that they continued to use strings of date pits as an aid to dhikr and tasbīḥ.
It is one of the lawful means of worship. Indeed, what is established from the Prophet (peace and blessings be upon him), namely that he counted tasbīḥ on his right hand, shows that it is permissible to count tasbīḥ with whatever helps a Muslim keep track of the number. There is therefore no basis for calling it an innovation (bidʿah), and we know of no jurist who said so.
Al-Ḥāfiẓ al-Suyūṭī (may Allah have mercy on him) wrote a dedicated treatise on the subject titled al-Minḥah fī al-Subḥah, printed within al-Ḥāwī li’l-Fatāwī (vol. 4–6).
Shaykh al-Islām Imam Ibn Ḥajar al-Haytamī (may Allah have mercy on him) was asked: Does the subḥah have a basis in the Sunnah? He replied: “Yes, and al-Ḥāfiẓ al-Suyūṭī wrote on this. Among the evidence is what is authentically reported from Ibn ʿUmar (may Allah be pleased with them both): ‘I saw the Prophet (peace and blessings be upon him) counting tasbīḥ on his hand.’ Ibn Abī Shaybah, Abū Dāwūd, and al-Tirmidhī also narrated: ‘Hold fast to tasbīḥ, tahlīl, and taqdīs, and do not be heedless, lest you forget the affirmation of Allah’s oneness (tawḥīd). Count them on the fingertips, for they will be questioned and made to speak.’ Counting tasbīḥ with pebbles, date pits, and a knotted string has also been reported from a group of the Companions and those after them. Some scholars held that counting on the fingertips is better than the subḥah, based on the ḥadīth of Ibn ʿUmar. Others distinguished, saying: if the one reciting is safe from miscounting, counting on the fingertips is better; otherwise the subḥah is better.” [al-Fatāwā al-Fiqhiyyah al-Kubrā, Vol.1/p.152]. And Allah Almighty knows best.