How we must ever be ready to do violence to ourselves.
A certain elder was once asked, "What is the meaning of this which is written: 'Strait is the gate and narrow is the way which leadeth unto life?" He answered, "The strait and narrow way is this : that a man do violence to his thoughts and destroy his own will for God's sake. This is what we are told the apostles did, of whom it is written: 'Lo, we have left all and followed Thee."
Reference: http://www.archive.org/details/wisdomofdesert00birmrich