In this episode we continue our discussion of Article IX “I Believe in the Holy Catholic Church, The Communion of Saints.” We focus specifically on the first mark of the Church which is that it is “One.” In addition to reading the Catechism, we also look at the Summa Theologica where St Thomas asks “Whether to be Head of the Church is proper to Christ” (IIIa. Q. 8, a. 6) We also look at the treatment concerning the one-ness of the Church in the Compendium Theologiae where St Thomas says that the Church is one in Faith, Hope and Charity.