Is Salat al-Istisqa legislated?

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The prayer for seeking rain is legislated. The view that the prayer and exit for it are not Sunnah, as held by Abu Hanifa, is incorrect. This opposing view is based on the Prophet, peace be upon him, supplicating from the pulpit on Friday without praying, and 'Umar supplicating with Al-'Abbas without praying. However, it is established through the narrations of 'Abdullah ibn Zayd, Ibn 'Abbas, and Abu Hurayrah that the Prophet, peace be upon him, exited and prayed. Their mention of supplication without prayer does not negate the established prayer, as performing both acts is permissible. Ibn al-Mundhir confirmed that the Prophet, peace be upon him, prayed the Prayer for Seeking Rain and delivered a sermon, which is the position of the majority of scholars except Abu Hanifa. Abu Yusuf and Muhammad ibn al-Hasan agreed with the rest of the scholars, and the confirmed Sunnah suffices against any differing opinion.