37 Sacred Scripture teaches the human family what the experience of the ages confirms: that while human progress is a great advantage to man, it brings with it a strong temptation. For when the order of values is jumbled and bad is mixed with the good, individuals and groups pay heed solely to their own interests, and not to those of others. Thus it happens that the world ceases to be a place of true brotherhood. In our own day, the magnified power of humanity threatens to destroy the race itself. For a monumental struggle against the powers of darkness pervades the whole history of man. The battle was joined from the very origins of the world and will continue until the last day, as the Lord has attested. Caught in this conflict, man is obliged to wrestle constantly if he is to cling to what is good, nor can he achieve his own integrity without great efforts and the help of God's grace. That is why Christ's Church, trusting in the design of the Creator, acknowledges that human progress can serve man's true happiness, yet she cannot help echoing the Apostle's warning: "Be not conformed to this world" (Rom. 12:2). Here by the world is meant that spirit of vanity and malice which transforms into an instrument of sin those human energies intended for the service of God and man. Hence if anyone wants to know how this unhappy situation can be overcome, Christians will tell him that all human activity, constantly imperiled by man's pride and deranged self-love, must be purified and perfected by the power of Christ's cross and resurrection. For redeemed by Christ and made a new creature in the Holy Spirit, man is able to love the things themselves created by God, and ought to do so. He can receive them from God and respect and reverence them as flowing constantly from the hand of God. Grateful to his Benefactor for these creatures, using and enjoying them in detachment and liberty of spirit, man is led forward into a true possession of them, as having nothing, yet possessing all things. "All are yours, and you are Christ's, and Christ is God's" (1 Cor. 3:22-23).
Source: Gaudium et Spes (Vatican.va)