A person may go on pondering deeply in intense emotion about his needs, about the need of the moment. That is not yet prayer. Adding "in the name of God" to it will not make it prayer. It is the cry of anguish which becomes a realization of God's mercy that constitutes prayer. It is the moment of a person in anguish forgetting his anguish and thinking of God and God's mercy. That is prayer.... It may last a moment but it is the essence of a lifetime.
Abraham Joshua Heschel: The Insecurity of Freedom with thanks to inward/outward
This comes very close to the heart of why I pray, and how I pray. For me, it is only this coming together of our human anguish and God’s mercy – which would be a possible description of the Cross – that makes prayer possible. If God were to allow me to feel the anguish of the world as keenly as he does, but were not to let me see how his mercy was poured out on the Cross, my despair would be beyond bearing, truly.
Perhaps this is why the Jesus Prayer, ‘Lord Jesus Christ, Son of God, have mercy on me, a sinner,’ is prayed so passionately so many years after it was first formulated in the time of the Desert Fathers and Mothers. I have written of this before, but I cannot think that I have seen the need for such a prayer more clearly than in these words of Heschel’s. The degree of anguish that we see in the world, that we suffer along with (which is what the word ‘compassion’ means) doesn’t permit any lesser prayer, and certainly cannot be comprehended in our words. I always think it was something like that that Paul was getting at when he wrote, in Romans 8.26-27: ‘Likewise the Spirit helps us in our weakness; for we do not know how to pray as we ought, but that very Spirit intercedes with sighs too deep for words. And God, who searches the heart, knows what is the mind of the Spirit, because the Spirit intercedes for the saints according to the will of God…’