An openness to the modern world in all aspects characterized the work of the Vatican Council II. Bernhard Häring was one of the key personalities of the Council and of its consequent theological development. The fundamental perspective of his moral theology is built on the integration of a posture that is both religious and ethical. On these elements he develops his moral reflection based on the concrete existence of the human being, on responsibility and love, where faith and life meet and complement one another. The present thesis seeks to present some considerations related to this theme, keeping in mind the challenges raised by Modernity and Post-Modernity. The phenomenon of moral conscience is very complex and, facing today s challenges, it becomes an extremely dynamic reality. Today, more than ever, the education of the moral conscience demands an overcoming of the assaults of modern individualism, while seeking an ethic of solidarity and a recognition of the profundity of life in all its aspects. The commitment of Christians finds its true form in doing what Jesus himself did. The Christian attitude is necessarily a persevering commitment to transform society, a pursuit of the acquisition of authentic human values, and a constant calling forth of the Reign of God. In this sense, a Christian ethical proposal for the 21st. Century must be at the same time the defender of the autonomy of human subjectivity and the objectivity of evangelical values.