At one time among others the Pope went to St. Clare's monastery in order to listen to her heavenly and divine conversation, for she was a shrine of the Holy Spirit...St. Clare meanwhile ordered loaves of bread to be set out on the tables for all the Sisters, for she wished to keep those loaves after they had been blessed by the Vicar of Christ.
The Pope answered: "Very faithful Sister Clare, I want you to bless those loaves of bread and to make over them the Sign of the Cross of Christ to whom you have offered yourself completely as a spotless sacrifice."
Then St. Clare, as a truly obedient daughter, very devoutly made the Sign of the Cross over those loaves of bread and blessed them. And a marvelous thing happened: all of a sudden a very beautiful and clearly marked cross appeared on all the loaves.
Saint Francis of Assisi
Little Flowers of St. Francis - 33