To imitate their teacher's actions. It was the job of a disciple to be like his teacher. A disciple's highest calling was to be a reflection of his teacher. His goal was to one day be just like his Master. A disciple studied to learn to act and to speak and to respond the same way his Master would act and speak and respond. A disciple studied to do the things his Master did. The gospels express this concept with the words, "Every disciple, fully trained will be like his master." (Luke 6:40)
To learn their teacher's traditions and interpretations. It was a disciple's job to learn the tradition of how his teacher kept the commands of God and interpreted the Scriptures. Every detail about the teacher was important to the disciple. The disciple needed to learn how the teacher washed his hands, how he kept the Sabbath, how he fasted, how he prayed, how he gave charity, how he affixed a mezuzah, how he said the blessings over food, etc. Furthermore, the way the teacher interpreted passages of scriptures, the meanings he drew out, the midrashim he told, the parables and stories he used to elucidate with, the way he explained a verse or understood a concept, each of these was of utmost importance to the disciple. Details of this sort were not just trivia. To a disciple, these were like gems and pearls meant to be gathered and treasured.
To memorize their teacher's words. It was the job of a disciple to memorize his teacher's words. The oral transmission process was the only method practiced among the sages. The great rabbis and Torah scholars did not write scrolls or compose books for their students to read and study. Instead, they taught orally and their disciples studied by memorizing their words. Through constant repetition, disciples memorized their teacher's words verbatim and were able to repeat them to subsequent generations.
