The History of Saint Clare, Virgin, tells of various miracles performed by Saint Clare. There are episodes of multiplications of loaves, of bottles of oil that appeared in the convent when there was none before.
But Clare performed the most famous of the miracles in 1240, on a Friday in September, in which she turned away an attack by Saracen soldiers who had broken into the convent cloister by showing them the Sacred Host.
This Eucharistic Miracle is cited in "The History of Saint Clare, Virgin," written by Tommaso da Celano, and describes how Saint Clare of Assisi succeeded with the Blessed Sacrament in turning away Saracen troops in the pay of Emperor Frederick II of Sweden.
The history goes like this: "By imperial order, regiments of Saracen soldiers and bowmen were stationed there, massed like bees, ready to desecrate the encampments and seize the cities.
Once during an enemy attack against Assisi, city beloved of the Lord, and while the army was approaching the gates, the fierce Saracens invaded San Damiano, entered the confines of the monastery and even the very cloister of the virgins.
The women swooned in terror, their voices trembling with fear as they cried to their Mother, Saint Clare.
with a fearless heart, commanded them to lead her, sick as she was, to the enemy, proceeded by a silver and ivory pyx in which the Body of the Saint of saints was kept with great devotion.
And prostrating herself before the Lord, she spoke tearfully to her Christ: 'Behold, my Lord, is it possible you want to deliver into the hands of pagans your defenseless handmaids, whom I have taught out of love for you?
I pray you, Lord, protect these your handmaids whom I cannot now save by myself.' Suddenly a voice like a child's resounded in her ears from the tabernacle: 'I will always protect you!' 'My Lord,' she added, 'if it is your wish protect also this city which is sustained by your love.' Christ replied, 'It will have to undergo trials, but it will be defended by my protection.' Then the virgin, raising a face bathed in tears, comforted the sisters: 'I guarantee you, daughters, that you will suffer no evil; only have faith in Christ.' Upon seeing the audacity of the sisters, the Saracens took flight and fled back over the walls they had scaled, unnerved by the strength of she who prayed.
And Clare immediately admonished those who heard the voice I spoke of above, telling them severely: 'Take care not to tell anyone about that voice while I am still alive, dearest daughters.'"