After David finishes school in Canterbury with Dr. Strong, Aunt Betsey asks him what it is that he wants to do with is life. With David being unsure of the answer, Betsey suggests that David take up an apprenticeship to become a proctor. Doctors' Commons is where David takes up his apprenticeship under Mr. Spenlow and Mr. Jorkins. During his apprenticeship, David enjoys a newfound sense of freedom living on his own in London. His aunt had an apartment arranged for him to stay in while he learned how to become a proctor. She also hired Mrs. Crupp to cook for David.

Doctors' Commons was a self-governing teaching body of practitioners of civil law. Members of Doctors' Commons had obtained doctorate degrees in civil law from either Oxford or Cambridge. Members of the governing body, called fellows, were elected from the advocates by existing fellows. In 1565, the society leased a site in Paternoster Row, which served as the headquarters until 1598. In 1568, the society moved to Knightrider Street. A couple of decades later, in 1858, Doctors' Commons was dissolved under terms of the Court of Probate and Matrimonial Causes Act of 1857. 

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The Editors of Encyclopaedia Brittanica. "Doctors' Commons." Encyclopaedia Brittanica, Encyclopaedia Brittanica, Inc., 8 Sept. 2020, www.brittanica.com/topic/Doctors-Commons.