Before entering upon the duties of his office, each attorney at law shall take and subscribe the following oath or affirmation before a person authorized to administer oaths: 'I do solemnly swear (or affirm) that I will support, obey and defend the Constitution of the United States and the Constitution of this Commonwealth and that I will discharge the duties of my office with fidelity, as well to the court as to the client, that I will use no falsehood, nor delay the cause of any person for lucre or malice.' Any person refusing to take the oath or affirmation shall forfeit his office.
Pennsylvania Legal Code