Bernard of Clairvaux speaks of a depth of prayer that can properly be called "death" - not a death to life, but a death to what holds us back from true life and union with God.
How I long often to be the victim of this death that I may escape the snares of death, that I may not feel the deadening blandishments of a sensual life, that I may be steeled against evil desire, against the surge of cupidity, against the goads of anger and impatience, against the anguish of worry and the miseries of care... How good the death that does not take away life but makes it better; good in that the body does not perish but the soul is exalted. - Bernard of Clairvaux
Bernard calls this deeper prayer of "death" contemplation.
This kind of ecstasy, in my opinion, is alone or principally called contemplation. Not to be gripped during life by material desires is a mark of human virtue; but to gaze without the use of bodily likenesses is the sign of angelic purity. Each, however, is a divine gift, each is a going out of oneself, each a transcending of self, but in one one goes much farther than in the other.
One of the main ways we open ourselves for this greater love to posses us is through prayer. We need to remember thought that the spiritual life is not primarily about certain practices of piety and techniques of prayer, but about a relationship. It's about responding to the One who has created and redeemed us, and who loves us with a love stronger than death, a love that desires to raise us from the dead. Much that is true of human relationships is also true of our relationship with God. Human relationships of friendship or marriage need time, attention, and care for them to continue and to grow. The same is true of our relationship with God. We have been called to union but we need to respond. As we turn to God in conversion or in a deeper awakening, besides turning away from deliberate sin - which deforms the soul, blocks the relationship and offends the Person who has sacrificed His life for us - we need to positively build the relationship by paying attention to God.
How great is the power of PRAYER!... I say very simply to God what I wish to say, without composing beautiful sentences, and He always understands me. For me, prayer is an aspiration of the heart, it is a simple glance directed to heaven, it is a cry of gratitude and love in the midst of trial as well as joy; finally, it is something great, supernatural, which expands my soul and unites me to Jesus. - St. Thérèse of Lisieux