Archbishop Sheen on 'the thrills of the Spirit' ...

... and the limits of studying about chastity from a book:

"When a people have lost sight of the meaning and purpose of life, they then attempt to find compensation in the intensity of their experiences, either revolutionary or personal. The 'thrill' is sought for itself. Real love attaches itself to a single, unique personality and remains loyal, nontransferable; but sexual enjoyment, if it is a goal in itself, leads to promiscuity. The ego can never love anything but itself; it 'loves' another person only so long as he or she is a source of selfish pleasure. Illicit love affairs are a very common method of trying to escape from God. The state of being in love is an attraction upward toward Love Itself, but unlawful, erotic love is merely another effort to find self-fulfillment without relinquishing the ego as our primary concern.* It is bound to fail. ...

"... Those who have never had any experience of intimate union with Divine Love sometimes deny the reality of the experience recounted in the Hound of Heaven. There are some things which have to be experienced to be known; the happiness of falling head over heels in love with God is one of these. As there are two ways of knowing chastity — by studying about it from a book, and by living purely — so there are two ways of knowing God — by studying about Him, and by incarnating His Truth into our lives. ...

"... Religion does not seem pleasant to those who have never climbed high enough, by a renunciation of selfishness, to glimpse its vistas; but a Divine Religion with the Holy Eucharist is much more pleasant to those who experience it than the world is to those who sin in it. It is possible that a true lover of God may have tasted both worlds, if he is a convert or a penitent, But the man who has lived only for the flesh, pleasure, and profit has no experience whatever of the thrills of the spirit. Since he has never tasted, he can never compare."

— Archbishop Fulton J. Sheen, Lift Up Your Heart (1950)