This Story is a good example about how our Mind can sabotage us.
A young man bet he could swim a mile wide river. As his friends watched him reach the middle of the river and pause. He stopped because he became afraid of what a Voice in his Mind said,
“This is too far, you can’t make it.”
He believed this thought and he turned around and swam back. Clearly he swam the full mile, yet he lost the bet because his thoughts created Fear. When he listened to this Voice in his Mind (the Shadow Side) those fearful thoughts stopped him from reaching his goal. Physically he was able – (obviously, he did swim a mile).
– Hal Robinson
Dancing Bear Teaching Lodge 