EWTN Catholic Q&A
titles for pope
Question from Lisa on 04-19-2005:

Went is meant by "Bark" of Peter?

Answer by Colin B. Donovan, STL on 04-26-2005:

A "Barque" is a kind of sailing vessel. The use of the term for the Church governed by the Successor of St. Peter refers directly to the New Testament image of Jesus being in Peter's boat, preaching from Peter's boat, and causing a miraculous catch of fish from Peter's boat (Lk. 5:3ff; John 21:3ff). These texts support the unique place of Peter in Christ's plan, amply testified to by Scripture as a whole.