This prayer is a means of seeking rain from Allah, the Exalted, during times of drought. That is, people are naturally disposed to ask help from the One Who is able to support them; Allah Alone. This prayer was known among the previous nations. It is regarded also as one of the acts of the prophets, peace be upon them all, as Allah, the Exalted, Says (what means): source www.islamweb.net
“And [recall] when Moses prayed for water for his people…” [Quran 2: 60]
Similarly, the Seal of Prophets, Prophet Muhammad sallallaahu `alayhi wa sallam ( may Allah exalt his mention ) performed Prayer for Rain for his people many times, and in many ways. In addition, Muslim scholars unanimously agree on the legality of such an act.
The Prayer for Rain is ordained during times of drought and times when rain fails, which causes harm to people. Then there is no way out except by supplicating their Lord and asking Him for water (rain). People may supplicate Allah in various ways. For instance, people may supplicate Allah in Prayer, whether in congregation or alone. They may also supplicate Him by invoking Him during the sermon of the Jumu’ah (Friday) Prayer, in which the Imam may invoke Allah, and Muslims say, “Ameen”.
Furthermore, it may be by invoking Allah, the Exalted, after performing prayers, or by supplicating Him in seclusions with neither prayer nor sermon. All such acts are related about the Prophet sallallaahu `alayhi wa sallam ( may Allah exalt his mention ).
The Prayer for Rain is regarded as a stressed Sunnah (Prophetic tradition) as ‘Abdullah Ibn Zayd may Allah be pleased with him said: “The Prophet sallallaahu `alayhi wa sallam ( may Allah exalt his mention ) went out to invoke Allah for rain. He faced the qiblah (the direction of Ka’bah in Mecca), invoking Allah. Then he reversed his cloak and performed two Rak’ahs (units of prayer) and recited the Quran aloud in them.”
[Al-Bukhari and Muslim]
