John Paul II presents Christ as the definitive answer to humanity’s questions about good, evil, meaning, and salvation, and Christian moral life as the freedom of those who live in the truth. The rich young man’s question introduces an account that joins the Decalogue and natural law to the Beatitudes, perfection, and communion with Christ. God is the source of goodness; love of God necessarily becomes concrete love of neighbour. Grace, the Holy Spirit, Baptism, and the Eucharist make faithful obedience possible, while the Church’s Magisterium preserves and interprets moral truth. Against relativism and autonomous conceptions of conscience, the encyclical teaches that natural law participates in God’s eternal law, that bodily acts have moral meaning, and that negative precepts prohibit intrinsically evil acts without exception. Conscience applies objective law but does not create it: sincere truth-seeking matters, invincible ignorance can lessen culpability, and negligence or habitual sin can deform judgment. The rejection of the “fundamental option” theory maintains that grave, deliberate acts can constitute mortal sin and cannot be justified by intention, circumstances, or consequences. Universal norms condemn fraud, theft, unjust wages, exploitation, and abuses of power, and warn that democracy without truth may become totalitarian. Theologians must serve Scripture, Tradition, and the Magisterium rather than reduce doctrine to opinion; bishops must teach, guard the faithful, administer the sacraments, and ensure that Catholic institutions retain their mission. The closing appeal entrusts the pursuit of holiness to Mary, Mother of Mercy.