To train the mind to move with the maximum speed and energy, with the utmost possible accuracy in the chosen direction, and with the minimum of disturbance or friction. That is Magick. To stop the mind altogether. That is Yoga.
Sit still. Stop thinking. Shut up. Get out! The first two of these instructions comprise the whole of the technique of Yoga. The last two are of a sublimity which it would be improper to expound in this present elementary stage.
The two seem, at first glance, to be opposed, but when you have advanced a little in both, you find that concentration learned in Yoga is of immense use in attaining the mental powers necessary in Magick; on the other hand, the discipline of Magick is of the greatest service in Yoga.