Saint Clare not at all ecumenical, defeated the Muslim army with the Blessed Sacrament

«The impious Frederic had already made Europe ring with the report of his cruel deeds, and insolent resistance to the Holy See. Not satisfied with the ravages committed by his own troops, he called the Moors to his assistance ; and himself, nominally a Christian, dyed his soul yet deeper in crime by urging their barbarism to wreak itself especially on the Papal States. His most sacred oaths to Honorius, his coronation by the hands of the Pope in Home, were alike forgotten; and when Gregory the Ninth reluctantly placed him under the Church's censure, his proud spirit sought to revenge itself by unheard-of outrages. The valley of Spoleto was already filled with these savage troops, and the Moors, thirsting for Christian blood, were encamped beneath the walls of Assisi. The terrified nuns ran trembling to the cell of their Mother, on whom years of ceaseless austerity and the heavy cares of her office had now done their work: she had long lain on a bed of painful sickness. But her holy zeal for the Divine honor thus insulted, and her maternal love, aroused the courage of her heart. In spite of the remon- strances of her children, who trembled for her precious life, she caused herself to be carried to the church, and there, prostrate before the Blessed Sacrament, she poured forth her prayer. In a few moments she arose, and with a supernatural strength proceeded to the battlements of the convent but not alone. In her hand she held the Eemonstrance, and bore in it the Sacramental Presence of her God. When the savage army beheld the light and glory which streamed forth from it, they ceased their wild shouts and yells of ex- ecration, and fell back trembling and dismayed. It is related in the Chronicles of the Order, that while St Clare lay prostrate before of Saints were still left to the devoted city. Clare as- sembled her religious. " My sisters," she exclaimed, "the inhabitants of this city provide daily for our necessities. It would indeed be impiety if we did not aid them to the utmost of our power in this extremity." Then, with ashes on their heads, the troop of conse- crated virgins prostrated themselves before God, and asked His mercy for their fellow-citizens. Their prayer was heard. That night the Assisians attacked their besiegers, and the army of Vitalis was completely routed. Shortly after, he perished miserably. Again the weak had conquered the strong, and the spiritual arms of fasting and prayer had inflicted death-wounds on the pride of earthly greatness. The cloistered nun had vanquished the crested warrior; and if the results of the prayers of religious persons are not always so manifest, should we therefore doubt their value and efficacy? How much is hidden which will one day be revealed ! how much despised which will one day be exalted ! Men ask for visible signs of the utility of a cloistered life for some tangible result of hours of prayer and contemplation. Incidents, such as that which we have just recorded, are not often manifested to the world, but it were scarcely wise to conclude that they are therefore less frequent.(The life of Saint Francis of Assisi, and a sketch of the Franciscan order)

«The Saracens besieged Assisi and made preparations to scale the walls of the Convent. St. Clare, who was sick at the time, had herself carried to the gates of the convent, where, with the Ciborium, containing the Blessed Sacrament, in her hands, prostrating herself in company with all her religious, she cried aloud: "O Lord, do not give into the hands of the infidels the souls of those who acknowledge and praise Thee. Protect and preserve Thy handmaidens whom Thou hast redeemed with Thy precious blood." A voice was distinctly heard, saying: "I will protect you always." The result proved that this was the voice of heaven. The Saracens, seized with a sudden fear, betook themselves to flight, those who had already scaled the walls, became blind, and flung themselves down. Thus were St. Clare and her religious protected and the whole city preserved from utter devastation, by the piety and devotion of the Saint to the Blessed Sacrament. (St. Clare, Virgin and Abbess by Father Francis Xavier Weninger, 1876)

Saracen is one of the names that medieval Christianity generically called Arabs or Muslims. The words "Islam" or "Muslim" were not introduced in European languages until the seventeenth century, using expressions like "law of Muhammad," Mohammedan, Ismailis, Hagarenes, Moors, etc.