This the second part of the phrase that begins with "Love is the Law." "Love magickally directed, and used as a spiritual formula," says Crowley. This is an important clarification for what otherwise has commonly been interpreted as justification for a kind of "free love" movement. As a "spiritual formula" it is a concise instruction for Sex Magick as practiced by the G∴B∴G∴
"Will," of course is the True Will of the Higher Self, while Sex is the engine of energy to be directed by the True Will in fulfillment of our goal.