3.5.2 Energy driven
We are all children of the sun, born on a planet flung from its glowing vapour as a ball of molten gas; children of light too, for the sun's ultra-violet rays then heated up a rich complex of molecules in the sea which one day mutated into the ancestors of all later life on earth, and created the protective layer of ozone that allowed the process of evolution to run its course.
Among the different shafts of light which St Francis reflected perhaps the most original lit up the entire natural context of our existence and the creatures we share it with. Before him, Christians had interpreted Genesis as entitling them to treat all other forms of life as their slaves; he, in contrast, believed that as works of God they should be respected and loved no differently from men.
He could not know that all visible life was dependent for its energy on solar power, filtered through the ozone, and trapped by the plants for general circulation through the food chain. Nevertheless observant, responsive to beauty and a visionary, he noticed wherever he went, the miraculous effects of the sun's light, warmth, and cycle of seasons.
The metaphor of light for God, common to so many thinkers, poets and mystics, suggests an analogue between it and the modern concept of energy, fundamental to all existence and activity, terrestrial and astral.
This is a proposition uncannily similar to the view propounded by some of the world's leading physicists.  
Studying astronomy provides the basic information each person needs to understand where he or she comes from and where the human race is going. There are universal questions: every religion in the world has a cosmology and they all contain a grain of truth; modern science brings a new and much more complete version of cosmology. The British Astronomer Royal, Sir Martin Rees, then goes on to expound the Big Bang theory of creation.
Our universe came into being as a minuscule speck of brilliant light. It was almost infinitely hot, and inside this fireball was contained the whole of space. And with the creation of space came the birth of time.
In fact the theories of modern science are not all so 'new'. About six years after Francis of Assisi died, Canon Henri d'Avranches wrote a versification of Thomas of Celano's life of the saint. In a flight of fancy he evokes the dialogue St Francis had with the Sultan of Egypt, which includes this passage.
He reasons . . .
How it is that all things come from one source, how a moment
Of that first principle is simple substance, a simple
Moment in the present, a substance simpler than
A mathematical point; how its essence is wondrously present
Wholly, always and everywhere outside of place and time.