In the G∴B∴G∴ this phrase is spoken as the opening of your ritual from the center of the Circle. It has the power of similar phrases like "Man your Stations" and "Let the Games Begin!" Note there are three admonitions—that the rituals are to be performed rightly, and with joy and beauty.
This is not a idle statement; indeed, nothing said or done in your magickal circle, or temple, is done without full awareness and intention to do anything less than your best and that is not only right action, but the feeling of joy and happiness in your heart, and the intention that all your movements, gestures, words, and thoughts will be done with the intention of grace and beauty.
How you think when doing Magick will affect how it works, and you want joy in your heart and beauty in our world.