How many times should the supplication for rain (Istisqa) be repeated if rain is not immediately granted?
Chapter on the Prayer for Rain (Istisqa)
Al-Mughni
Book of the Eclipse Prayers (Solar and Lunar)
Primary text
If rain is not granted, the people should return for the supplication on the second and third day. This is the opinion held by Malik and Al-Shafi'i. The evidence for repetition is that it represents the utmost striving in supplication and humility. The Prophet (peace be upon him) stated: "Indeed, Allah loves those who persist in supplication."
Supporting text
Ishaq held that they should only go out once because the Prophet (peace be upon him) only went out one time. Instead of going out repeatedly, they should gather in their mosques after the prayer to remember Allah, supplicate, and the Imam should supplicate on the pulpit during Friday prayer while the people say 'Amen'. The Prophet (peace be upon him) did not go out a second time because his request was answered immediately upon his first excursion, and the first time going out is more strongly established by the Sunnah than subsequent times.