The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1253

Abdullah b. Abu Qatada reported on the authority of his father: While we said our prayer with the Messenger of Allah (may peace be upon him) he heard tumult. (At the end of the prayer) he (the Holy Prophet) said: What is the matter with you? They said: We hastened to prayer. He (the Holy Prophet) said: Don't do that; when you come for prayer, there should be tranquillity upon you. Pray (along with the Imam) what you can find and complete what preceded you.

Source materials are from the University of Southern California MSA site
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