Matriculation marks the formal admission of a student to membership of the University, and a College may not normally allow an unmatriculated student to be a resident member of the College ('in statu pupillari') after the Division (that is, the mid-point) of his or her first term of residence.
Every candidate for matriculation must subscribe to the following declaration by signing the Matriculation Registration Form:
I promise to observe the Statutes and Ordinances of the University as far as they concern me, and to pay due respect and obedience to the Chancellor and other officers of the University.
You can find the Statutes and Ordinances here.
A person is deemed to be matriculated from the beginning of the term in which a completed Matriculation Registration Form and satisfactory evidence of his or her qualification to matriculate is known by the College.