I have asked a marriage official to conclude my marriage since I have no proxy and, being an adult, I can act as the proxy of myself, but he refused. What should I do?
All perfect praise be to Allah the Lord of the Worlds. May Allah`s peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
In order for a marriage to be valid there must be a Wali (Guardian) for the woman: father, brother, paternal uncle or any paternal relative. If there isn`t any, then the judge can act as the woman`s guardian and conclude the marriage contract. And Allah The Almighty Knows Best.
Is it permissible for the big brother to force his sisters to wear Hijjab (Islamic wear) if their father didn`t do his part in this regard ?
All Perfect Praise is due to Allah, The Lord of The Worlds
The father`s attention should be drawn gently and politely, and the sisters should also be reminded with good words since Allah, The Almighty, Says (What means): "O ye who believe! Save yourselves and your families from a Fire whose fuel is Men and Stones." [Al-Tahreem/6]. And Allah Knows Best.
Is it permissible to swear by (Allah "The Living")?
Yes, it is permissible because "The Living" is one of Allah`s Attributes.
What is the torment of the grave?
We seek refuge in Allah from the torment of the grave. The important point is that the cause of the torment of the grave is disbelief or committing sins without repentance. It affects the soul, and the body is impacted by it, even if we do not see it. And Allah Knows Best.