NOTES for Lev 18:1-30
The Book of Leviticus gives special attention to the norms and rules connected with keeping the seventh commandment, with what today is usually called sexual morality. Not because the society in which it appeared was somehow puritanical or prudish, but because sex is connected with far more in human life than people usually think. Today sex and sexuality most often appear to us as something purely physiological, something that can bring problems or pleasure, and sometimes both at once.
Yet God's original design for humanity did not include sex as something purely physiological and separate from the fullness of life intended for human beings; and God certainly never intended sex to become something forbidden, shameful, or unclean for human beings. Sexuality was meant to become one of the instruments for building relationships between people, an instrument very important from the standpoint of human nature and of the union of two people at the natural level.
This is not only about physiology; it is about the whole of human nature as a whole. It is no accident that the energy manifested in the sexual sphere proves so universal: it can be transformed into practically any other kind of physical or psychological energy connected with human nature. It is no surprise that a normal, full spiritual life and the sanctification of a person are unthinkable without the involvement of sexual energy in this process.
Such involvement, however, is possible only when a person does not abuse his possibilities in matters of sexual life and does not regard sex solely as a source of pleasure that he can dispose of at his own discretion. This is precisely what the seventh commandment is aimed at; this is its deep meaning. Of course, the protection of family and marital relationships is important here too, but it is only one element of a more complex and more extensive task.
The task itself is connected with involving human nature in the process of that spiritual and natural transformation which the Bible calls transfiguration. The beginning of transfiguration is sanctification, the partial and usually temporary change in human nature that was possible before the coming of Christ. This is precisely the task the Book of Leviticus has in mind when it prescribes fairly strict regulation of sexual life.