What is I‘tikaf, and how is it performed?
I‘tikaf is staying in the mosque with the intention of I‘tikaf. It is fulfilled by remaining in the mosque for a period that qualifies as devotion or seclusion (I‘tikaf). It is recommended (Sunnah) for anyone entering the mosque to intend I‘tikaf as long as they remain inside.
What is the ruling on istinja' after urination, and is it done with water and soap or with water only?
Istinja' from urine and stool is obligatory. It is permissible to perform istinja' with water alone, or with toilet paper alone. The best way is with toilet paper then water. If one wishes to suffice with one of them, then water is better. And Allah the Almighty knows best.
What is the ruling of Islam on swearing by Allah without intending to take an actual oath?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
If someone swears by Allah without intending to take an actual oath, and without the firm resolve to bind themselves to it, then there is no sin or expiation (Kaffarah) required of them. Allah the Exalted says {what means}: 'God will not call you to account for thoughtlessness in your oaths, but for the intention in your hearts; and He is Oft-forgiving, Most Forbearing.' [Al-Baqarah/225]. However, a Muslim should avoid swearing oaths excessively so that their tongue does not become accustomed to it. Allah the Exalted says {what means}: 'And make not God’s (name) an excuse in your oaths against doing good, or acting rightly, or making peace between persons; for God is One Who heareth and knoweth all things.
' [Al-Baqarah/224]. And Allah the Exalted knows best."
How many rak‘ahs are there in Tarawih prayer?
The most complete form of Tarawih prayer consists of twenty rak‘ahs, excluding Shaf‘ and Witr. This is the opinion of the majority of scholars, both past and present, and it is the practiced tradition in the two Holy Mosques.
However, Tarawih is valid with any even number of rak‘ahs, even two rak‘ahs, as long as it is performed with the intention of Qiyam al-Ramadan.