A Thrush, seeking food, stayed too long on a branch as was caught even when it knew better. Men feel worst when they contribute to their own undoing.
A man walking and concentrating accidentally stepped on a viper which bit him. Concentrate on one thing to the exclusion of others at your own peril.
A Thrush’s mother disapproved of her son’s friendship with a Swallow. The Thrush and Swallow live at different seasons. One would kill the other. Know the nature of those you deal with.