Chapter: While offering the Istisqa prayer, people should raise hands along with the Imam

A bedouin came to Allah's Messenger (ﷺ) on a Friday and said, "O Allah's Messenger ! The livestock, the offspring, and the people have perished." So, Allah's Messenger (ﷺ) raised both his hands invoking Allah (for rain) and the people too raised their hands with Allah's Messenger (ﷺ) invoking Allah (for rain). We had not left the mosque when it started raining. It rained till the next Friday when the same man came to Allah's Messenger (ﷺ) and said, "O Allah's Messenger! The travelers are compelled to postpone their journeys (because of excessive rain) and the roads are overflowed."

The narrator Anas added that the Prophet (ﷺ) raised his hands (during the invocation) to such an extent that the whiteness of his armpits was visible.