4.30.63). Augustine himself was a good model of this practice. Before the preaching, he invited the congregation to pray (Epistula 29). After the sermon he also prayed (Sermones 153.1). For Augustine’s homiletics, the time of prayer is the most precious time, because that time is a time when all the audience meets God the Truth, and through that time they can understand the truth of God more fully. Prayer is a major means of grace in knowing God. Augustine says that love is the most important discipline in Christian life in his sermon, De disciplina christiana. If one adds another to Christian discipline besides love, prayer will come first. The preacher should be a good example of all sermons. The manner of life can be an eloquent sermon (copia dicendi, forma vivendi; DDC 4.29.61). In most of the cases, it seems to be true that the sermon of a preacher cannot be better than his or her life, but vice versa seems also to be true: the sermon cannot be worse than the preacher’s life. The more a preacher endeavors after humility, discipline, and love, the better his or her sermon becomes. And now these three are always necessary for all Christian teachers: humility, discipline, and love. But the greatest of these is love. For "the goal of this command is love" (1 Tim. 1:5 cited in DDC 1.26.27; 1.35.39; 1.40.44; 4.28.61). Hugh of St. Victor Hugh of St. Victor (died 1141) in the Middle Ages laid down three conditions for a sermon: that it should be "holy, prudent and noble", for which, respectively, he required sanctity, knowledge and eloquence in the preacher. François Fénelon stipulated "must prove, must portray, must impress" (Second Dialogue). St. Augustine's work "De rudibus catechizandis". St. Gregory the Great's "Liber regulæ pastoralis" is still extant, but is inferior to St. Augustine's; it is rather a treatise on pastoral theology than on homiletics. Hincmar says that a copy used to be given to bishops at their consecration. In the ninth century Rabanus Maurus (died 856), Archbishop of Mainz, wrote a treatise De institutione clericorum, in which he depends much on St. Augustine. In the twelfth century Guibert, Abbot of Nogent (died 1124), wrote a famous work on preaching entitled "Quo ordine sermo fieri debet". This is one of the historical landmarks in preaching. It is replete with judicious instruction; it recommends that preaching should be preceded