Prince Alphonso, eldest son of Edward I, was to marry Margaret, daughter of Florent V, Count of Holland, in 1284, but he died before the wedding. This psalter is thought to have been commissioned by Edward I for his son's marriage because of the heraldry painted at the beginning of Psalm 1. The decoration was left unfinished until the early 14th century, when it was filled out in various styles. The Alphonso Psalter would have been used as a personal prayerbook. Around the time it was made, the first books of hours, special prayerbooks for the laity, were being created. The first letter of Psalm 52 was decorated in the early 14th century. Its vine ornament is inhabited by a pair of red dragons who threaten to devour it--typical early 14th century book art. The large letter serves to mark one of the divisions of the psalter. To organise the cycle of prayer that monks and devout lay people recited on a daily basis, the psalter was divided into eight sections: seven for the prayers said very early in the morning (matins) and one for evening prayers (vespers). On the lower part of the page's frame a conventional grotesque grows a plant from its tail, possibly to entertain the reader or to show how easily he or she could be distracted.