[youtube]http://www.youtube.com/embed/CgTTpGIT2QY[/youtube]
http://dhspriory.org/thomas/Serm14Attendite.htm St. Thomas Aquinas preached this academic sermon, Attendite (which means "Beware!"), on the Third Sunday after the Feast of the Apostles Saints Peter and Paul, July 26, 1271, at the University of Paris. The topic is false prophets, which Jesus warns us about in St. Matthew 7:15-16: "Take ye great heed (attendite) of false Prophets, which come to you in the clothing of sheep, but inwardly are ravening wolves. By their fruits you shall know them." The first part is the sermon itself, given in the morning, and the second part is the "collatio" or "collation," given at vespers time (sundown).