About this passageThe final chapter of the book, and the one that argues least from the movement's causal claim and most from ordinary observation. Allen treats calmness as the product of practised self-control rather than temperament. The passage does also promise that tranquillity brings commercial success, which is worth noticing as part of what the tradition holds.
Calmness of mind is one of the beautiful jewels of wisdom. It is the result of long and patient effort in self-control. Its presence is an indication of ripened experience, and of a more than ordinary knowledge of the laws and operations of thought.
A man becomes calm in the measure that he understands himself as a thought evolved being, for such knowledge necessitates the understanding of others as the result of thought, and as he develops a right understanding, and sees more and more clearly the internal relations of things by the action of cause and effect he ceases to fuss and fume and worry and grieve, and remains poised, steadfast, serene.
The calm man, having learned how to govern himself, knows how to adapt himself to others; and they, in turn, reverence his spiritual strength, and feel that they can learn of him and rely upon him.
The strong, calm man is always loved and revered. He is like a shade-giving tree in a thirsty land, or a sheltering rock in a storm.
In plainer words
A calm mind, Allen says, is one of the finest things a person can have, and it is the result of long patient work on yourself rather than luck. Someone becomes calm as they come to understand themselves — and, through that, other people — so they stop fussing and fuming and worrying and stay steady instead. A calm person has learned to govern themselves, which is why others trust them. He compares such a person to a tree giving shade in a dry place, or a rock you can shelter behind in a storm.
A restatement in modern English, written for this collection. The passage above is the text; this is one way of putting it.