"Life work" means that to which one will devote one's energies. It is the world of the soul, as well as the material work done in the visible world. These categories of tasks are not separate: they are not inimical to one another any more than sweeping the temple, washing the vestments, or cleaning and arranging the altar are inimical to the act of prayer. On the contrary, these tasks are prayer. They are the work of the soul in that they provide a suitable atmosphere for the cultivation of a contemplative and receptive attitude.
Breathing is one internal function that the conscious mind can control with comparative ease. The effect of controlled breathing is almost like communication with all conscious parts of one's being saying to them, "Simmer down and listen; there is something beyond the turmoil". It is communication in action that often works when words merely go in one ear and out the other, not even changing the cognitive mind. In essence, the effect is to turn all the elements of our will toward stillness and waiting.