St. Augustine (354-430) was one of the most prolific and influential writers of the early Christian Church. Some of his many writings were among the bare essentials which every medieval monastic library ought to own. His commentary on the 150 Psalms was often written in three volumes (which would have covered Psalms 1-50, 51-100, and 101-150 respectively) of which this is the second. It has an inscription stating that it was written under Arnulf, Prior of Rochester; by 1107 he was no longer prior, so the manuscript must be earlier than that date.. The vast initial 'P' which opens the volume includes two men enmeshed with animals in foliage; the vertical trunk of the letter is formed of a hybrid dragon and interlace ornament with further animal heads. The lower margin has a typical 14th-century Rochester Ownership inscription naming Prior Arnulf.