"The world of sinful pleasure is transient because sin is a dark power and is the only thing that makes man mortal and transient. In reality, through every sin, man does the will of the creator of sin - the devil, whose will pulls man into death and transience. Sin, first of all , ravages, overturns, perverts the intellectual organs in man, and man becomes insane, declaring transient things, ideas, and passions as his deities, as his main concern, purpose, and meaning of life. This is the primary source of all man's idolatry: cultural, scientific, philosophical, artistic, political and religious.
In opposition to this stands the God-man, Who shows how man overcomes all transience and all deaths, and becomes immortal and eternal. But how does this happen? This happens by doing the will of God: he that does the will of God abides forever. Where is the will of God expressed? It is expressed in the God-man Christ and in His Holy Gospel. By fulfilling the Gospel, man fills himself with immortality, eternal life and becomes eternal. Who is the true immortal then? Only a true Christian." St. Justin (Popovich), Commentary on the Epistles of St. John the Theologian, 30.
"The world of Christians is of a special kind, their style of living, their thinking, their speech, and all their actions. That of this world is completely different. There is a great difference between them." St. Macarius the Great, The Fifty Spiritual Homilies, p. 63
Everyday you should try to plant in your soul something spiritual, which will eject something worldly and sinful ... replace the sinful images in your mind with holy ones. Replace songs with hymns, worldly magazines with spiritual books. If you do not break away from all that is worldly and sinful, if you do not commune with Christ, with Panaghia, with the Saints, with the Church Triumphant, and if you do not place yourself completely in the hands of God, you will not acquire spiritual health." Elder Paisios, Spiritual Awakening, pp. 104-105.