Pope Francis' new encyclical is filled with references to his namesake, whom the Pope says is a model of how an integral ecology goes beyond matters of science and leads humanity to find God in creation.

"I believe that Saint Francis is the example par excellence of care for the vulnerable and of an integral ecology lived out joyfully and authentically," the Pope wrote.

The saint, he said, "helps us to see that an integral ecology calls for openness to categories which transcend the language of mathematics and biology, and take us to the heart of what it is to be human."

St. Francis of Assisi is an Italian friar and preacher who founded the Order of Friars Minor, known more commonly as the Franciscans, in the early 1200s. He is the patron saint of all who study and work in the area of ecology, and is much loved by the faithful and non-Christians.

Pope Francis' new encyclical was published June 18. It's title "Laudato Si," meaning "Praise be to You," is taken from St. Francis of Assisi's medieval Italian prayer "Canticle of the Sun," which praises God through elements of creation like Brother Sun, Sister Moon, and "our sister Mother Earth."

Pope Francis revealed shortly after his 2013 election as Bishop of Rome that he had chosen his papal name in honor of the saint due to his emphasis on the poor. In the encyclical, the Pope says that we are called to embrace the same sense of wonder that St. Francis did when we encounter creation.

"Just as happens when we fall in love with someone, whenever (St. Francis) would gaze at the sun, the moon or the smallest of animals, he burst into song, drawing all other creatures into his praise," the Pope wrote.

Without this openness to "awe and wonder" when approaching nature and the environment, "our attitude will be that of masters, consumers, ruthless exploiters, unable to set limits on their immediate needs," he said.

"By contrast, if we feel intimately united with all that exists, then sobriety and care will well up spontaneously," he added, explaining that St. Francis' poverty and austerity were "no mere veneer of asceticism," but rather "something much more radical: a refusal to turn reality into an object simply to be used and controlled."

The Pope reflected that, with scripture as a basis, St. Francis extends a universal invitation "to see nature as a magnificent book in which God speaks to us and grants us a glimpse of his infinite beauty and goodness."

Rather than a problem to be solved, the world is a "joyful mystery" which ought to be contemplated with gladness and praise to God as the saint shows us, he said.

In the encyclical Pope Francis also pointed to the human person as being unique from the rest of creation since man is a being created in the image and likeness of God.

Human beings, he said, "possess a uniqueness which cannot be fully explained by the evolution of other open systems."

The unique personal identity of each person as well as man's ability to reason, develop arguments, interpret reality and create art as well as other "yet undiscovered capacities" are all signs that humanity possesses a uniqueness "which transcends the spheres of physics and biology."

Although humanity is unique within creation, it doesn't mean that others beings are "superfluous," he said, explaining that the whole material universe is an expression of God's love.

Everything from the soil, water and the mountains are like "a caress" from God and they show us the "boundless affection" God has for his creatures.

However, Francis cautioned that this doesn't "put all living beings on the same level," and nor does it "deprive human beings of their unique worth and the tremendous responsibility it entails."

Neither is it "a divinization of the earth," which the Pope said "would prevent us from working on it and protecting it in its fragility."

Pope Francis also speaks of the personal conversion needed on the part of each individual if we are to care for creation and the environment in an effective way.

Christians in particular, he said, must realize "that their responsibility within creation, and their duty towards nature and the Creator, are an essential part of their faith."

Again turning to the figure of St. Francis of Assisi, the Pope says that in looking to him we realize that "a healthy relationship with creation is one dimension of overall personal conversion, which entails the recognition of our errors, sins, faults and failures, and leads to heartfelt repentance and desire to change."

This conversion calls for attitudes which foster a spirit of generous and tender care, he notes, saying that this first of all requires both "gratitude and gratuitousness."

Christian spirituality, he said, "proposes an alternative understanding of the quality of life, and encourages a prophetic and contemplative lifestyle, one capable of deep enjoyment free of the obsession with consumption."

Such sobriety is "liberating" when lived both freely and consciously, the Pope says, observing that to live soberly doesn't mean one has a "lesser life" or that their life is lived with less intensity.

"On the contrary, it is a way of living life to the full. In reality, those who enjoy more and live better each moment are those who have given up dipping here and there, always on the look-out for what they do not have."

The Pope also noted that having inner peace is closely tied to care for the environment and the common good.

When lived with authenticity, this peace is reflected in a balanced lifestyle, which together with "a capacity for wonder," leads to a greater understanding of life, Francis said.

"An integral ecology includes taking time to recover a serene harmony with creation, reflecting on our lifestyle and our ideals, and contemplating the Creator who lives among us and surrounds us, whose presence must not be contrived but found, uncovered."

Because the universe reaches full fruition in God, a "mystical meaning" can be found in simple objects of nature, such as a leaf, a trail in the mountains, a dewdrop or even in "a poor person's face," Francis observed.

"The ideal is not only to pass from the exterior to the interior to discover the action of God in the soul, but also to discover God in all things."

At the end of the document, Pope Francis pointed to the sacraments as a concrete way in which God uses nature as a means of leading us to the supernatural life.

He noted how water, oil and fire are used in the sacraments as symbols of a spiritual reality.

"The hand that blesses is an instrument of God's love and a reflection of the closeness of Jesus Christ, who came to accompany us on the journey of life. Water poured over the body of a child in Baptism is a sign of new life," he said. He added that to encounter God doesn't mean running away from the world or "turning our back" on nature.

He noted how in the Eucharist God gives himself as food for the creatures he has saved, and has chosen to reach "our intimate depths" through a "fragment of matter," which is the bread and wine.

God, the Pope said, "comes not from above, but from within, he comes that we might find him in this world of ours."

Francis also drew attention to the role of Mary, who having cared for Jesus, now watches over "this wounded world" with pain and motherly affection.

"Just as her pierced heart mourned the death of Jesus, so now she grieves for the sufferings of the crucified poor and for the creatures of this world laid waste by human power," he said.

The Pope concluded his encyclical with an encouragement to imitate St. Francis and to "sing as we go," never letting our struggle and concern for the planet overshadow "the joy of our hope."

"God, who calls us to generous commitment and to give him our all, offers us the light and the strength needed to continue on our way."