"Because he tells us what the Church says," said the other smiling, "it is his business. He need not be any better or cleverer in other respects. The baker may be a thief or a foolish fellow; but his bread is good." "But how do you know," went on Isabel, who thought Mistress Margaret a little slow to see her point--"how do you know that the Church is right?" The old nun considered a moment, and then lifted her embroidery again. "Why do you think," she asked, beginning to sew, "that each single soul that asks God's guidance is right?" "Because the Holy Ghost is promised to such," said Isabel wondering. "Then is it not likely," went on the other still stitching, "that the millions of souls who form Holy Church are right, when they all agree together?" Isabel moved a little impatiently. "You see," went on Mistress Margaret, "that is what we Catholics believe our Saviour meant when He said that the gates of hell should not prevail against His Church." But Isabel was not content. She broke in: "But why are not the Scriptures sufficient? They are God's Word." The other put down her embroidery again, and smiled up into the girl's puzzled eyes. "Well, my child," she said, "do they seem sufficient, when you look at Christendom now? If they are so clear, how is it that you have the Lutherans, and the Anabaptists, and the Family of Love, and the Calvinists, and the Church of England, all saying they hold to the Scriptures alone. Nay, nay; the Scriptures are the grammar, and the Church is the dame that teaches out of it, and she knows so well much that is not in the grammar, and we name that tradition. But where there is no dame to teach, the children soon fall a-fighting about the book and the meaning of it." Isabel looked at Mistress Margaret a moment, and then turned back again to the window in silence. At another time they had a word or two about Peter's prerogatives. "Surely," said Isabel suddenly, as they walked together in the garden, "Christ is the one Foundation of the Church, St. Paul tells us so expressly." "Yes, my dear," said the nun, "but then Christ our Lord said: 'Thou art Peter, and on this rock I will build my Church.' So he who is the only Good Shepherd, said to Peter, 'Feed My sheep'; and He that is _Clavis David_ and that openeth and none shutteth said to him, 'I will give thee the keys, and whatsoever thou shalt bind on earth shall be bound in heaven.' That is why we call Peter the Vicar of Christ." Isabel raised her eyebrows. "Surely, surely----" she began.