Hadith 1408
Ishaq bin Abdullah (may Allah have mercy on him) narrates that a certain governor sent me to ask Sayyiduna Ibn Abbas (may Allah be pleased with both of them) about the Salat al-Istisqa (prayer for rain) of the Messenger of Allah (peace and blessings be upon him). He replied that the Messenger of Allah (peace and blessings be upon him) went out wearing simple and old clothes, weeping and expressing humility and humbleness. He (peace and blessings be upon him) did not deliver a sermon like your sermon. And he (peace and blessings be upon him) led two units (rak‘ahs) of prayer.