After many chapters, St. Teresa de Jesus finally begins to describe what she calls the "prayer of quiet". This is not the same as mental prayer. Mental prayer, as discussed, means actually thinking about God while you pray.
What Teresa calls "the prayer of quiet" is what some would call "consolation," the experience that God is directly responding to our prayer with a feeling of spiritual rapture. It is a state of prayer that God sends on us. We have to be praying to receive it, but we have no guarantee that it will come in any circumstances. Sometimes, we may get it instantly after some very weak prayers; other times, we may make a retreat worth of prayers and devotions and sacraments and yet not experience "the prayer of quiet."
"This is a supernatural state, and, however hard we try, we cannot reach it for ourselves; for it is a state in which the soul enters into peace, or rather in which the Lord gives it peace through His presence, as He did to that just man Simeon.[107] In this state all the faculties are stilled. The soul, in a way which has nothing to do with the outward senses, realizes that it is now very close to its God, and that, if it were but a little closer, it would become one with Him through union. This is not because it sees Him either with its bodily or with its spiritual eyes. The just man Simeon saw no more than the glorious Infant -- a poor little Child, Who, to judge from the swaddling-clothes in which He was wrapped and from the small number of the people whom He had as a retinue to take Him up to the Temple, might well have been the son of these poor people rather than the Son of his Heavenly Father. But the Child Himself revealed to him Who He was. Just so, though less clearly, does the soul know Who He is. It cannot understand how it knows Him, yet it sees that it is in the Kingdom (or at least is near to the King Who will give it the Kingdom), and it feels such reverence that it dares to ask nothing. It is, as it were, in a swoon, both inwardly and outwardly, so that the outward man (let me call it the "body", and then you will understand me better) does not wish to move, but rests, like one who has almost reached the end of his journey, so that it may the better start again upon its way, with redoubled strength for its task.
The body experiences the greatest delight and the soul is conscious of a deep satisfaction. So glad is it merely to find itself near the fountain that, even before it has begun to drink, it has had its fill. There seems nothing left for it to desire. The faculties are stilled and have no wish to move, for any movement they may make appears to hinder the soul from loving God. They are not completely lost, however, since, two of them being free, they can realize in Whose Presence they are. It is the will that is in captivity now; and, if while in this state it is capable of experiencing any pain, the pain comes when it realizes that it will have to resume its liberty. The mind tries to occupy itself with only one thing, and the memory has no desire to busy itself with more: they both see that this is the one thing needful and that anything else will unsettle them. Persons in this state prefer the body to remain motionless, for otherwise their peace would be destroyed: for this reason they dare not stir. Speaking is a distress to them: they will spend a whole hour on a single repetition of the Paternoster. They are so close to God that they know they can make themselves understood by signs. They are in the palace, near to their King, and they see that He is already beginning to give them His Kingdom on earth. Sometimes tears come to their eyes, but they weep very gently and quite without distress: their whole desire is the hallowing of this name. They seem not to be in the world, and have no wish to see or hear anything but their God; nothing distresses them, nor does it seem that anything can possibly do so. In short, for as long as this state lasts, they are so overwhelmed and absorbed by the joy and delight which they experience that they can think of nothing else to wish for, and will gladly say with Saint Peter: "Lord, let us make here three mansions."[108]" (Way of Perfection Ch. 31, paras. 2 & 3; emphasis added).
It strikes me that, when I experience the "prayer of quiet," at first, it is no longer possible to "actively" pray. I may mutter prayers with my mouth or "recite them" in my head, but they can only be truly "rote" prayers. I can't actively meditate. I can't think of causes to pray for. I can only repeat little prayers and enjoy basking in God's embrace.
But, after a short time, it is much *easier* to pray. If, for example, I experience the prayer of quiet after Communion, it can often be almost like an ecstasy, but I know what's going on around me. I could have been struggling with paying attention all through Mass, and now, suddenly, I'm hit with the prayer of quiet, and prayer becomes extremely easy for me.
While I could easily stay in church for another 15 or 20 minutes praying, I usually have to leave to tend to my family. But, if I have experienced "the prayer of quiet," I can resume my daily living while continuing in a prayerful state.