The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1889

Abu Wa'il reported: 'Ammar delivered to us the sermon. It was short and eloquent. When he (, Ammir) descended (from the pulpit) we said to him: 0 Abd al-Yaqzn, you have delivered a short and eloquent sermon. Would that you had lengthened (the sermon). He said: I have heard the Messenger of Allah (may peace be upon him) as saying: The lengthening of prayer by a man and the shortness of the sermon is the sign of his understanding (of faith). So lengthen the prayer and shorten the sermon, for there is charm (in precise) expression.

Source materials are from the University of Southern California MSA site
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