With the Bull Quia maior Pope Innocent III proclaimed the Fifth Crusade in 1213.
"For how can a man be said to love his neighbor as himself, in obedience to God's command, when, knowing that his brothers, who are Christians in faith and in name, are held in the hands of the perfidious Saracens. . . does not do something effective to liberate them."
Following are excerpts from Quia maior:
Because at this time there is a more compelling urgency than there has ever been before to help the Holy Land in her great need and because we hope that the aid sent to her will be greater than that which has ever reached her before, listen when, again taking up the old cry, we cry to you. We cry on behalf of him who when dying cried with a loud voice on the cross, becoming obedient to God the Father unto the death of the cross, crying out so that he might snatch us from the crucifixion of eternal death. He also cries out with his own voice and says, "If any man will come after me, let him deny himself and take up his cross and follow me," as if to say, to put it more plainly, "If anyone wishes to follow me to the crown, let him also follow me to the battle, which is now proposed as a test for all men."
Oh, how much good has already come from this cause! How many men, converted to penance, have delivered themselves up to the service of the Crucified One in order to liberate the Holy Land and have won a crown of glory as if they had suffered the agony of martyrdom, men who perhaps might have died in their wicked ways, ensnared in carnal pleasures and worldly enticements! This is the ancient device of Jesus Christ which he has deigned to renew in these times for the salvation of his faithful.
For how can a man be said to love his neighbor as himself, in obedience to God's command, when, knowing that his brothers, who are Christians in faith and in name, are held in the hands of the perfidious Saracens in dire imprisonment and are weighed down by the yoke of most heavy slavery, he does not do something effective to liberate them, thereby transgressing the command of that natural law which the Lord gave in the gospel, "Whatsoever you would that men should do to you, do you also to them?" Or perhaps you do not know that many thousands of Christians are being held in slavery and imprisonment in their hands, tortured by countless torments?
We are sure that, since we ought to put much more trust in divine mercy than in human power, we ought to fight such a conflict not so much with physical arms as with spiritual ones.
Fasting and almsgiving should be joined to prayer, so that with these wings the prayer itself may fly more easily and quickly to the most loving ears of God, who will mercifully listen to us at the appointed time. And every day during the celebrations of Mass . . . the priest who is celebrating must chant this prayer over the altar:
"God, who disposes all things with marvelous providence, we humbly beseech thee to snatch from the hands of the enemies of the cross the land which thine only-begotten son consecrated with his own blood and to restore it to Christian worship by mercifully directing in the way of eternal salvation the vows of the faithful here present, made for its liberation, through the same Christ Our Lord."
The full text of Quia maior can be read here.