"the full power of worship will only be felt if its sacramental character is realized in undiminished form"

"the full power of [the Christian (73)] worship [that is irreversibly 'the deepest of the springs by which leisure is fed and continues to be vital' (69-70) but that 'cannot be "done" for the sake of' leisure (72)] will only be felt if its sacramental character is realized in undiminished form, that is, if the sign is fully visible.  In leisure, as was said, man oversteps the frontiers of the everyday workaday world, not in external effort and strain, but as though lifted above it in ecstacy.  That is the sense of the visibility of the sacrament:  that man is 'carried away' by it, thrown into 'ecstacy'.  Let no one imagine for a moment that that is a private and romantic interpretation.  The Church has pointed to the meaning of the incarnation of the Logos in the self-same words:  ut dum visibiliter Deum cognoscimus, per hunc in invisibilium amorem rapiamur, that we may be rapt into love of the invisible reality through the visibility of that first and ultimate sacrament:  the Incarnation."

Joseph Pieper, Leisure:  the basis of culture, trans. Alexander Dru (San Fransisco:  Ignatius Press, 2009 [1963/1952]) , 73-74.  The Latin is from the Preface of the Nativity (Octave of Christmas, i.e. Christmas Day through Epiphany Eve, with the exception of the Feast of St. John), and goes back to the Gregorian Sacramentary (nos. 38, 51, and 1537) at least.  See The Gregorian sacramentary under Charles the Great:  edited from three mss. of the 9th century by H. A. Wilson, Henry Bradshaw Society 49 (London:  Henry Bradshaw Society, 1915), :

for through the mystery of the Word made flesh thy splendour has shone before our mind's eye with a new radiance, and through him whom we recognize as God made visible we are carried away in love of things invisible

(The MIssal in Latin and English, being the text of the Missale Romanum with English rubrics and a new translation (New York:  Sheed & Ward, 1959), 763).