Material beings are moved from without, like billiard balls; but spiritual beings are moved from within.

The first cause of a specifically human act is always internal, not external. By “a specifically human act” I mean one like asking a question, creating a work of art, making a moral choice, affirming another person, or appreciating the beauty of nature — or praying. Mind moves itself from within, actively; matter is moved from without, passively. That is why thought is where the action starts.

Saint Paul knew this principle too. He knew that in order to become saints, in order to bring our whole lives into captivity to Christ, we must first “take every thought captive to obey Christ” (2 Cor 10:5).

The point and purpose of life is to become a saint, to become Christlike. Leon Bloy wrote: “Life holds only one tragedy: not to have been a saint.”

Excerpt from Prayer For Beginners by Peter Kreeft