The whetstone that hones your senses sharp.
The teacher that tells you once.
The wild horse that is chased
Then ridden, but not broken.

The safety-catch to play with.
The tooth-ache to be probed.
That last mistake, regretted.
That nagging voice, insistent.

Your ego seat-belt.
Your sanity-check.
Your heartbeat-throttle.
Your life-respect.