From the catechetical instructions by Saint John Mary Vianney, priest
The glorious duty of man: to pray and to love

My little children, reflect on these words: the Christian's treasure is not on earth but in heaven. Our thoughts, then, ought to be directed to where our treasure is. This is the glorious duty of man: to pray and to love. If you pray and love, that is where a man's happiness lies.

Prayer is nothing else but union with God. When one has a heart that is pure and united with God, he is given a kind of serenity and sweetness that makes him ecstatic, a light that surrounds him with marvelous brightness. In this intimate union, God and the soul are fused together like two bits of wax that no one can ever pull apart. This union of God with a tiny creature is a lovely thing. It is a happiness beyond understanding.

We had become unworthy to pray, but God in his goodness allowed us to speak with him. Our prayer is incense that gives him the greatest pleasure.

My little children, your hearts are small, but prayer stretches them and makes them capable of loving God. Through prayer we receive a foretaste of heaven and something of paradise comes down upon us. Prayer never leaves us without sweetness. It is honey that flows into the soul and makes all things sweet. When we pray properly, sorrows disappear like snow before the sun.

Prayer also makes time pass very quickly and with such great delight that one does not notice its length. Listen: Once when I was a purveyor in Bresse and most of my companions were ill, I had to make a long journey. I prayed to the good God, and, believe me, the time did not seem long.

Some men immerse themselves as deeply in prayer as fish in water, because they give themselves totally to God. There is no division in their hearts. O, how I love these noble souls! Saint Francis of Assisi and Saint Colette used to see our Lord and talk to him just as we talk to one another.

How unlike them we are! How often we come to church with no idea of what to do or what to ask for. And yet, whenever we go to any human being, we know well enough why we go. And still worse, there are some who seem to speak to God like this: "I will only say a couple of things to you, and then I will be rid of you." I often think that when we come to adore the Lord, we would receive everything we ask for, if we would ask with living faith and with a pure heart.

From a Spiritual Canticle by Saint John of the Cross, priest
I give myself as your spouse for ever

The soul united to God and transformed in him draws from within God a divine breath, much like the most high God himself. And God, abiding in the soul, breathes forth the life of the soul as its exemplar. This I take to be what Paul meant when he said: Because you are children of God, God has sent the Spirit of his Son into your hearts, crying, "Abba, Father"; this is what takes place in those who have achieved perfection.

One should not wonder that the soul is capable of so sublime an activity. For if God so favors her that she is made God-like by union with the most Holy Trinity, I ask you then, why it should seem so incredible that the soul, at one with the Trinity and in the greatest possible likeness to it, should share the understanding, knowledge and love which God achieves in himself.

How this is possible no other power or wisdom can express, save by explaining how the Son of God obtained this sublime state for us and won for us the power to be the children of God, as he asked of the Father:Father, I desire that where I am those you have given me may also be with me, that they may see the glory you have given me, that is, that they may share with certainty the very task I perform.

And then he said: "Not for them alone do I ask but also for those who will come to believe in me through their teaching, that all may be one as you, Father, are one in me and I in you, that they may be one in us; that the world may believe that you have sent me. And the glory you have given me I have given them that they may be one as we are. I in them, you in me, that they may be made perfect, and the world will know that you sent me and as you have loved me, so I have loved them.

The Father thus gives them the same love he shares with the Son, though not by nature as with the Son, but through unity and transformation of love. One should not think that the Son is asking the Father to make the saints one with him in essence and nature as the Son is with the Father, but rather that they be united with him in love, just as the Father and Son are one in the essential unity of love. Accordingly, souls possess the same goods by participation that the Son possesses by nature. As a result, they are truly divine by participation, equals and companions of God.

Thus Peter said: May grace and peace be perfected in you in the knowledge of God and Christ Jesus our Lord. For all things of his divine power, which are given to us for our life and goodness, are given through the knowledge of him who called us to his own glory and power, by which he has given us great and precious promises, that by these we may be made partakers of the divine nature. So the soul, in this union which God has ordained, joins in the work of the Trinity, not yet fully as in the life to come, but nonetheless even now in a real and perceptible way.

O my soul, created to enjoy such exquisite gifts, what are you doing, where is your life going? How wretched is the blindness of Adam's children, if indeed we are blind to such a brilliant light and deaf to so insistent a voice.