What is the expiation for perjury?
Perjury is forbidden and one of the major sins that require turning to Allah in repentance, seeking His forgiveness, giving back rights to whom they belong, or seeking their forgiveness, and expiating for that oath.
What are the Sharia consequences when the sacrificial time for the uḍḥiyyah comes to an end?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
If the sun sets at the end of the last of the Days of Tashrīq and the sacrificial animal (uḍḥiyyah) has not yet been slaughtered, then its prescribed time has elapsed. Should one slaughter it thereafter, it will not be considered a valid uḍḥiyyah.
However, if the sacrifice was vowed (mandhūrah), then it remains obligatory to slaughter it — and it shall be carried out as a make-up (qaḍā') of the vow, with its meat distributed in the rightful channels designated for such sacrifices.
It is stated in Bushrā al-Karīm (p. 702): "If one slaughters after the sunset of the last of the Days of Tashrīq... it isn`t considered a valid uḍḥiyyah, unless it was vowed — in which case it is carried out as qaḍā'."
And Allah Almighty knows best.
What is the ruling on performing istinja' with perfumed tissues or a tissue moistened with water?
Performing istinja' with perfumed or moistened tissues is not sufficient if they are not dry, due to the moisture on them reaching the impurity, which increases its spread rather than reducing it. Then, to remove the impurity, one must use pure water. And Allah the Almighty knows best.
What is the ruling on offering an Udhiyah on behalf of another with their permission?
Praise be to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is permissible for a person to offer a sacrifice (Udhiyah) on behalf of someone else with their permission, even if the person performing it has not offered a sacrifice for themselves. It is stated in Sharh Manhaj al-Tullab (Vol.5/P.261) by Zakariya al-Ansari: "No one may offer a sacrifice on behalf of another without their permission... as opposed to when permission has been granted." And Allah the Almighty knows best.