The reason why the grace of Baptism is not preserved is because the order, rules, and laws of an upbringing which is adopted to this end are not kept. The chief causes of this are:
1) Going away from the Church and its grace-giving means. This starves the sprout of Christian life, disconnecting it from its sources, and it wilts as a flower wilts when it is placed in a warm place.
2) Failure to pay heed to one's bodily nature. People think that the body may be developed in every way without harm for the soul, while actually in the bodily members is the seat of the passions, which develop together with its development, become rooted in and take possession of the soul. Penetrating the bodily members, the passions receive in them a place to settle, or they make out of them a certain unapproachable fortress and thereby secure power for themselves for all the time to come.
3) A development of the powers of the soul which is undiscriminating and is not directed towards a single aim. People do not see the aim ahead of them, and so do not see the path to it. From this, despite all the concern for the most contemporary education, people do no more than to puff up in themselves curiosity, self-will, and a thirst for pleasures.
4) Complete forgetfulness of the spirit. Prayer, fear of God, and conscience are seldom taken into consideration. If there is outward good order, the most inward side of life is always taken for granted and therefore always left to take care of itself. During the time of learning, the most important thing is covered over by secondary things, and the one thing needed is overshadowed by a multitude of others.
5) Finally, when one enters into the age of youth without first putting in place good principles and the determination to live in a Christian way. Further, when one does not restrain the attractions of youthful life in a proper order, but gives oneself over to all the thirst for impressions, through amusements, light reading, the heating of the imagination by fantasies, indiscriminate contact with those who are like oneself, and especially with the opposite sex, an exclusive concern for learning and giving oneself over to the world by means of fashionable ideas, rules, and customs, which are never favorable to the life of grace but always arm themselves hostilely against it and strive to smother it.
Each one of these causes, and even one of them, is sufficient to quench in a young person the life of grace. But it happens for the most part that they act together, and one unfailingly draws another in its wake; and they all together so obstruct the spiritual life that sometimes not even the slightest trace of it can be noticed, as if a man has no spirit at all and was created not for communion with God, does not have the powers foreordained for this, and has not received the grace which gives him life.
Excerpt from "The Path To Salvation" By Saint Theophan The Recluse .