Did the Prophet, may God’s prayers and peace be upon him, use the miswak before every two rak’ahs of Qiyam al-Layl, or did he use the miswak once for all the prayers of Qiyam al-Layl?

Encouragement to use the miswak is authentically established from the Prophet, peace and blessings be upon him, and it is emphasized when rising for prayer. This includes the two rak'ahs of Tarawih, because they are prayers encompassed by the generality of his saying, peace and blessings be upon him: "Were it not that I would cause hardship for my nation, I would have commanded them to use the miswak with every prayer." Some scholars have mentioned its desirability for every two rak'ahs of Tarawih.