Work here is meant in the Kantian, or Christian, or Buddhist sense of work.
Dedication to a goal/target is dedication to something you dont have an thus must gain/achieve. Once you have gained this thing that was external to you, you no longer have need for effort/willfullness, thus, you, no longer need to exist. This coincides with the above view (you should not forget yourself in your work) because dedication to work detached you from yourself, because you are unfree - you have self derived principles to abide by, self determined laws to adhere to, and goals to achieve - thus you have forgotten yourself in your laws, principles and goals. The longer the work goes on for, the more you forget your true self, your true freedom.