I had forgotten about the Barque of Peter. It is the emblem of the Year of Faith and a long-running theme in Catholic theology. It harks back to the stories of Jesus and the disciples in the storm on the Sea of Galilee. The church is seen as the barque of Peter, which will bring us all safely home.
Mark 4:35-41 – Authorized (King James) Version
35 And the same day, when the even was come, he saith unto them, Let us pass over unto the other side. 36 And when they had sent away the multitude, they took him even as he was in the ship. And there were also with him other little ships. 37 And there arose a great storm of wind, and the waves beat into the ship, so that it was now full. 38 And he was in the hinder part of the ship, asleep on a pillow: and they awake him, and say unto him, Master, carest thou not that we perish? 39 And he arose, and rebuked the wind, and said unto the sea, Peace, be still. And the wind ceased, and there was a great calm. 40 And he said unto them, Why are ye so fearful? how is it that ye have no faith? 41 And they feared exceedingly, and said one to another, What manner of man is this, that even the wind and the sea obey him?