<p style='text-align: justify;'>This manuscript of the <i>Pupilla Oculi</i> by John de Burgo (fl. 1370–1398) is a pastoral handbook intended for parish priests. It summarises the church’s penitential and sacramental laws so that they could be understood and applied in practice. The text is derived from the <i>Oculus sacerdotis</i> by William of Paull or de Pagula (fl. early fourteenth century).</p><p style='text-align: justify;'>De Burgo divided his work into ten parts. These are: I) The sacraments in general; II) Baptism; III) Confirmation; IV) The Eucharist; V) Penitence and sentences of excommunication; VI) Extreme unction; VII) Holy orders; VIII) Marriage; IX) Tithes, sanctuary, wills, clerical residence, and similar matters; and X) Practical theology, including the Ten Commandments, the seven deadly sins, and works of mercy. Trinity Hall’s copy ends during part 8.</p><p style='text-align: justify;'><i>Pupilla Oculi</i> was likely written between 1380 and 1385, when for part of that time John de Burgo was Chancellor of the University of Cambridge. Some forty manuscript copies survive. Cambridge was an important centre for the production and dissemination of <i>Pupilla Oculi</i> throughout the 15th century.</p>