St. Hilary observes, that singleness of heart is the most necessary condition of faith and true virtue, "For Christ teaches that only those who become again as it were little children, and by the simplicity of that age cut off the inordinate affections of vice, can enter the kingdom of heaven. These follow and obey their father, love their mother; are strangers to covetousness, ill-will, hatred, arrogance, and lying, and are inclined easily to believe what they hear. This disposition of affections opens the way to heaven. We must therefore return to the simplicity of little children, in which we shall bear some resemblance to our Lord's humility."[29] This, in the language of the Holy Ghost, is called the foolishness of the cross of Christ,[30] in which consists true wisdom. That prudence of the flesh and worldly wisdom, which is the mother of self-sufficiency, pride, avarice, and vicious curiosity, the source of infidelity, and the declared enemy of the spirit of Christ, is banished by this holy simplicity; and in its stead are obtained true wisdom, which can only be found in a heart freed from the clouds of the passions, perfect prudence, which, as St. Thomas shows, is the fruit of the assemblage of all virtues, and a divine light which grace fails not to infuse. This simplicity, which is the mother of Christian discretion, is a stranger to all artifice, design, and dissimulation, to all views or desires of self-interest, and to all undue respect or consideration of creatures. All its desires and views are reduced to this alone, of attaining to the perfect union with God. Unfeignedly to desire this one thing, to belong to God alone, to arrive at his pure love, and to do his will in all things, is that simplicity or singleness of heart of which we speak, and which banishes all inordinate affections of the heart, from which arise the most dangerous errors of the understanding. This is the essential disposition of every one who sincerely desires to live by the spirit of Christ. That divine spouse of souls, loves to communicate himself to such.[31] His conversation (or as another version has it, his secret) is with the simple.[32] His delight is in those who walk with simplicity.[33] This is the characteristic of all the saints:[34] whence the Holy Ghost cries out, Approach him not with a double heart.[35] That worldly wisdom is not subject to the law of God, neither can it be.[36] Its intoxication blinds men, and shuts their eyes to the light of divine revelation. They arrogate to themselves the exclusive privilege of learning and clear understanding: but the skepticism, the pitiful inconsistencies, and monstrous extravagances, which characterize their writings and discourses, make us blush to see so strong an alliance of ignorance and presumption; and lament that the human mind should be capable of falling into a state of so deplorable degeneracy. Among the fathers of the church we admire men the most learned of their age, the most penetrating and most judicious, and at the same time { 147} the most holy and sincere; who, being endowed with true simplicity of heart, discovered in the mysteries of the cross the secrets of infinite wisdom, which they made their study, and the rule of their actions.