The Inmost is one with the Inmost; yet the form of the One is not the form of the other; intimacy exacts fitness. He therefore who liveth by air, let him not be bold to breathe water. But mastery cometh by measure: to him who with labour, courage, and caution giveth his life to understand all that doth encompass him, and to prevail against it, shall be increase. "The word of Sin is Restriction": seek therefore Righteousness, enquiring into Iniquity, and fortify thyself to overcome it.

Appendix VI : A few principal rituals – Liber Reguli. - Magick Book IV : Liber ABA - Part III : Magick in Theory and Practice (1929)