Paul VI, Apostolic Exhortation Gaudete in Domino Nº 8

Technological society has succeeded in multiplying the opportunities for pleasure, but it has great difficulty in generating joy. For joy comes from another source. It is spiritual. Money, comfort, hygiene and material security are often not lacking; and yet boredom, depression and sadness unhappily remain the lot of many. These feelings sometimes go as far as anguish and despair, which apparent carefreeness, the frenzies of present good fortune and artificial paradises cannot assuage. Do people perhaps feel helpless to dominate industrial progress, to plan society in a human way? Does the future perhaps seem too uncertain, human life too threatened? Or is it not perhaps a matter of loneliness, of an unsatisfied thirst for love and for someone's presence, of an ill-defined emptiness? 

2 Timothy 4,1-5

I charge you in the presence of God and of Christ Jesus, who willjudge the living and the dead, and by his appearing and his kingly power: proclaim the word; be persistent whether it is convenient or inconvenient; convince, reprimand, encourage through all patience and teaching.
For the time will come when people will not tolerate sound doctrine but, following their own desires and insatiable curiosity, will accumulate teachers and will stop listening to the truth and will be diverted to myths. But you, be self-possessed in all circumstances; put up with hardship; perform the work of an evangelist; fulfill your ministry.

Jude 17-23

But you, beloved, remember the words spoken beforehand by the apostles of our Lord Jesus Christ, for they told you, "In (the) last time there will be scoffers who will live according to their own godless desires." These are the ones who cause divisions; they live on the natural plane, devoid of the Spirit.

But you, beloved, build yourselves up in your most holy faith; pray in the holy Spirit. Keep yourselves in the love of God and wait for the mercy of our Lord Jesus Christ that leads to eternal life. On those who waver, have mercy; save others by snatching them out of the fire; on others have mercy with fear, 14 abhorring even the outer garment stained by the flesh.

Encyclical Letter Ad Petri Cathedram Nº 6, Author: John XXIII

All the evils which poison men and nations and trouble so many hearts have a single cause and a single source: ignorance of the truth—and at times even more than ignorance, a contempt for truth and a reckless rejection of it. Thus arise all manner of errors, which enter the recesses of men's hearts and the bloodstream of human society as would a plague. These errors turn everything upside down: they menace individuals and society itself.

Second Timothy 4, 1-5

Before God and before Christ Jesus who is to be judge of the living and the dead, I charge you, in the name of his appearing and of his kingdom: proclaim the message and, welcome or unwelcome, insist on it. Refute falsehood, correct error, give encouragement -- but do all with patience and with care to instruct. The time is sure to come when people will not accept sound teaching, but their ears will be itching for anything new and they will collect themselves a whole series of teachers according to their own tastes; and then they will shut their ears to the truth and will turn to myths. But you must keep steady all the time; put up with suffering; do the work of preaching the gospel; fulfil the service asked of you.