There are two sorts of mental prayer; one common and easy, the other very special, extraordinary and advanced, something received rather than made….There is a very great difference between these two sorts of prayer: the former may in some pleasure be taught by words, the second we cannot so teach, because no words are able to express it. It is a hidden manna, which no man knoweth but him that receiveth it.  Even the receiver cannot explain how it is, nor even properly understand how it is, as Cassian well deserves, quoting to this effect what he calls a divine and heavenly saying of the blessed St. Antony Abbot: ‘Prayer is not perfect as long as the monk at prayer is aware of the very fact that he is praying.’…we cannot express what this prayer is, nor teach it to others, but you must not seek to apply yourself to it, nor raise yourself to it if God does not raise you; apply you and lift you up to it. That would be great pride and presumption, and you would be deprived of the grace of prayer that you deserved, and be left without any. ‘He hath led me’, says the Spouse, ‘into His cellar’ (Cant., ii. 4).    This entry which God gives to the soul into His privacy, and into His wine cellar, to sate and inebriate her with His love, is a most particular gift of the Lord: the Bride did not go in by herself, no, not until her beloved took her by the hand and led her in.  The lifting of yourself up to the kiss of His mouth is not a thing you can or ought to do, unless He Himself lifts you up.  It would be great impertinence and audacity…
–St Alphonsus Rodriquez, ‘On Christian Perfection’.

The well-known Jesuit, Brother Alphonsus Rodriguez, used to say his Rosary with such fervor that he often saw a red rose come out of his mouth at each Our Father and a white rose at each Hail Mary. The red and white roses were equal in beauty and fragrance, the only difference being in their color.  –St. Louis De Montfort  ‘The Secret of the Rosary’