Is it permissible for a person who had vowed to give a certain amount of money to another, but didn`t find the latter to donate that money to the mosque?
In principle, the vowing person should abide by his vow as much as possible. Therefore, if he couldn`t find the person that he had made the vow for, then the vow itself is countless and nothing is due on its maker. However, if the latter happens to find the former later on then, he has to give him that money.
Is Zakah (obligatory charity) due on land intended for selling?
Yes, lands intended for trade are valued, and Zakah is paid according to their estimated value after a lunar year had lapsed, but if the owner didn`t pay the due Zakah, then he should do so after selling them.
Is permissible to buy/sell with non-Muslim?
Yes buying/selling for a Muslim with non-Muslim is permissible as regards what is lawful.
An Arab young man had an illegitimate sexual relationship with a Christian American while she was staying in one of the Arab countries. After she returned to America, she told him that she had doubts that she was impregnated by him. It is worth pointing that it is hard for him to get a visa to the USA. What is the ruling of Sharia on this?
All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Zina (Adultery and extramarital relations) is one of the grave sins that incur the wrath of Allah if the adulterer didn`t make immediate repentance. However, the child isn`t attributed to the adulterer. Rather, he/she is attributed to the woman who got pregnant by him and, according to Sharia, it isn`t considered a legitimate child of the adulterer. And Allah The Almighty Knows Best.