Q 2: Is it permissible
for a married person who becomes Junub (in a state of post-sexual ritual impurity) after having sexual intercourse with his wife at night to perform Fajr (Dawn) Prayer without making Ghusl (full ritual bath)?
Salah (Prayer) is not valid without Taharah (ritual purification). Anyone who offers Salah without Taharah, his Salah is invalid. Allah (Exalted be He) states:
O you who believe! When you intend to offer As-Salât (the prayer), wash your faces and your hands (forearms) up to the elbows, rub (by passing wet hands over) your heads, and (wash) your feet up to ankles. If you are in a state of Janâba (i.e. after a sexual discharge), purify yourselves (bathe your whole body).
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.