Surdas was an eager student who wanted to learn about Spirituality. He met a Guru who accepted him as his disciple. The Guru found that Surdas was hampered by his quality of getting angry easily, which prevented him from learning. Thus, the Guru decided to make Surdas shed his anger.
The Guru asked Surdas to chant God's name while doing all his activities for one month and then meet him. Surdas followed the Guru's instructions and the day after one month, he went to meet his Guru. On his way to Guru's ashram, a sweeper on the street carelessly put dirt on his clothes. Surdas got angry and scolded the sweeper. He went home, changed clothes and then met his Guru.

To his surprise the Guru told  Surdas that he was not yet ready to learn and he had to chant and do his chores for another month.  Surdas returned sadly, and continued to chant God's name for another month while doing his chores.

After a month, he eagerly went to his Guruji's ashram and same thing happened again. Surdas again became really angry and blamed the sweeper. After bathing, he met his Guru who asked Surdas to chant God's name for one more month. One month passed away and this time the same incident happened when Surdas went to meet his Guru. However, this time Surdas addressed him softly saying "Thank you. You are my master. You have helped me to overcome my anger." The sweeper felt bad for his action.

This time as Surdas approached his Guru's hermitage, he could see his Guru standing in front of the hermitage welcoming him. Guru told Surdas that he is now ready to teach him. Surdas could now understand the process he went through.

Moral of the story:

1) A Guru knows what a student is lacking of and knows the ways that would teach him.
2) As a student, you must have faith in Guru's words and follow them with devotion.  

Related links-

Article on Guru Shishya