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.
I`m keeping a plot of land (10 Dunums) for my children. Is it liable for Zakah?
Praise be to Allah, The Lord of the Worlds.
Land that is purchased with the intention of ownership and personal benefit—meaning to retain it for use and not for trade—is not subject to zakāh, as such property is not considered from trade commodities (ʿurūḍ al-tijārah).
It is stated in Al-Ḥāwī al-Kabīr:
“If it is property and one intends it for trade, then zakāh is due upon it; but if he intends it for personal possession, then no zakāh is due upon it.” And Allah, the Exalted, knows best.
What is the ruling on istinja' after urination, and is it done with water and soap or with water only?
Istinja' from urine and stool is obligatory. It is permissible to perform istinja' with water alone, or with toilet paper alone. The best way is with toilet paper then water. If one wishes to suffice with one of them, then water is better. And Allah the Almighty knows best.
Is the marriage, which lacks a valid legal contract, a guardian, and a court registration, valid?
It is incumbent that a valid marriage contract be concluded in the presence of a guardian and two trustful witnesses, and it should be registered in the court to protect the rights of the wife. Actually, a valid marriage contract is what differentiates between sound marriage and fornication.