Homily and catechesis, although distinct in their complex identities and in their purpose, arising from the one source kerygmatic and flow together towards the unification of the formation processes of believers. As we survey the history of catechetical thought, easily emerge the nature, tasks and purposes of their catechesis, so that the distinction with the Homily appears clear, precise and incontrovertible. This distinction has been highlighted several times by the Church’s Magisterium repeatedly by Vatican Council II and was confirmed by the Apostolic Exhortations Evangelii gaudium and Verbum Domini. The homily is a communicational ritual that implies his full immersion in the anthropological-cultural contexts; for this reason, it is now necessary to study the homily from an interdisciplinary perspective with the Communication Sciences.