Why was the exact date of Laylat al-Qadr concealed?
The wisdom behind this is to encourage Muslims to strive in worship throughout all the nights of Ramadan, or at least in the last ten nights. By doing so, they will earn the reward of observing Laylat al-Qadr as well as the reward of worshiping on other blessed nights.
Does post-natal bleeding (Nifas) stop before forty days after childbirth?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
Yes, post-natal bleeding (Nifas) can cease before the completion of forty days. If the bleeding stops completely and its return is not expected, the woman has attained ritual purity (Taharah), even if forty days have not yet passed. And Allah the Exalted knows best.
Is it valid to perform Tarawih prayer at home?
It is Sunnah for a Muslim to perform Tarawih prayer in congregation at the mosque.
However, if a person sometimes prays it at home in congregation with their family for a valid reason, there is no harm in doing so.
Can someone who begins a voluntary fast break it?
It is preferable for someone who begins an act of worship not to break it.
Allah the Exalted has said {what means}: "and let not your [good] deeds come to nought!" [Muhammad/33].
However, if a person starts a voluntary fast (nafl) and needs to break it, they are going against what is preferable, but there is no sin upon them.