There is a passage, in the 3rd movement, beginning at bar 168, marked F in the score. Here the orchestra calms down and what follows is full of serenity. I think this is one of those magical moments in the symphonies of Brahms. Have you ever noticed how extraordinary these bars are? In the following link, it is at 2:45:
http://www.youtube.com/watch?v=fhmJr-LOYNE
http://www.youtube.com/watch?v=fhmJr-LOYNE
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