From Pope St. John Paul II’s encyclical Veritatis Splendor (1993):
“Teacher, what good must I do to have eternal life?”. The question of morality, to which Christ provides the answer, cannot prescind from the issue of freedom. Indeed, it considers that issue central, for there can be no morality without freedom: “It is only in freedom that man can turn to what is good”.56 But what sort of freedom? The Council, considering our contemporaries who “highly regard” freedom and “assiduously pursue” it, but who “often cultivate it in wrong ways as a licence to do anything they please, even evil”, speaks of “genuine” freedom: “Genuine freedom is an outstanding manifestation of the divine image in man. For God willed to leave man ‘in the power of his own counsel’ (cf. Sir 15:14), so that he would seek his Creator of his own accord and would freely arrive at full and blessed perfection by cleaving to God”.57 Although each individual has a right to be respected in his own journey in search of the truth, there exists a prior moral obligation, and a grave one at that, to seek the truth and to adhere to it once it is known.58 As Cardinal John Henry Newman, that outstanding defender of the rights of conscience, forcefully put it: “Conscience has rights because it has duties”.59
Certain tendencies in contemporary moral theology, under the influence of the currents of subjectivism and individualism just mentioned, involve novel interpretations of the relationship of freedom to the moral law, human nature and conscience, and propose novel criteria for the moral evaluation of acts. Despite their variety, these tendencies are at one in lessening or even denying the dependence of freedom on truth.
If we wish to undertake a critical discernment of these tendencies — a discernment capable of acknowledging what is legitimate, useful and of value in them, while at the same time pointing out their ambiguities, dangers and errors — we must examine them in the light of the fundamental dependence of freedom upon truth, a dependence which has found its clearest and most authoritative expression in the words of Christ: “You will know the truth, and the truth will set you free” (Jn 8:32).
56 Second Vatican Ecumenical Council, Pastoral Constitution on the Church in the Modern World Gaudium et Spes, 17.
58 Cf. Second Vatican Ecumenical Council, Declaration on Religious Freedom Dignitatis Humanæ, 2; cf. also Gregory XVI, Encyclical Epistle Mirari Vos Arbitramur (August 15, 1832): Acta Gregorii Papæ XVI, I, 169-174; Pius IX, Encyclical Epistle Quanta Cura (December 8, 1864): Pii IX P.M. Acta, I, 3, 687-700; Leo XIII, Encyclical Letter Libertas Præstantissimum (June 20,1888): Leonis XIII P.M. Acta, VIII, Romæ 1889, 212-246.
59 A Letter Addressed to His Grace the Duke of Norfolk: Certain Difficulties Felt by Anglicans in Catholic Teaching (Uniform Edition: Longman, Green and Company, London,1868-1881), vol. 2, p. 250.
— Veritatis Splendor 34