It was during the summer of 1858 that Brahms met Agathe von Seibold.  He had gone to visit Ise Grimm at Göttingenm the university town where Joachim spent his holidays.  Ise had recently married, and his home was a meeting place for the younger musicians.

I have invited some people in this evening,” he told Johannes on the latter’s arrival.  “Not a party!” he hastened to add, knowing his friends taste.  “There will be music.  Unfortunately Joachim doesn’t get back from England until next week, but we shall have a fair quartet, and perhaps Agathe von Seibold will sing.  She is one of my harmony pupils, and she has a good voice too.

Fräulein Agathe was shy and rather plain.  When he was first introduced to her, Hannes was not particularly attracted to the girl.  But when she began to sing (one of his songs, too!) he saw her in a different light. 

“You have a beautiful voice, Fräulein,” he said earnestly.  “And you sing with such a delicate feeling!”

Agathe flushed with pleasure.  To have a compliment from Herr Brahms – a really well-known musician!  Her heart beat so fast that she could find no words with which to answer.

“I shall have to write some songs for you,” the young composer continued.  “Will you sing them with me?”

Brahms always had a weakness for lovely voices – particularly if they belonged to young and charming girls.  All the women he loved could sing.  Even Clara Schumann was a fair contralto, and on more than one occasion joined his women’s choruses.

During the weeks following, Johannes and Agathe saw much of each other.  One day he found her struggling over an exercise in composition which his friend Ise had given her.  Music-writing was not Agathe’s strong point.  “Herr Grimm scolds me for making so many mistakes,” she admitted to her new friend.

“He does!” cried Johannes mischievously.  “Well – let’s astonish him this time.”

He sat down and wrote out the exercise for her.  Agathe copied it and proudly carried the sheet to her teacher.  But Her Grimm’s reaction was not what she expected. Instead of showing pleased surprise, he cried indignantly: “But this is terrible! How on earth did you ever come to write such pitiable rubbish?”

Poor Agathe published and finally stammered: “What if Johannes wrote it?” “Then,” answered Ise, “it would be still worse!”

Suddenly the two looked at each other and burst out laughing.  They realized Brahms had been fooling them both.

Source:Goss, Madeleine & Schauffler, Robert (1943) Brahms The Master. New York: Henry Holt and Company, pp.159-161.