This verse is very difficult for anyone, either with or without morality. For what men nowadays call Vice is really virtue -- virtue, manliness -- and Virtue -- cowardice, hypocrisy, prudery, chastity, and so on are really vices -- vitia, flaws.
Mohammed struck at the root of the insane superstition of tabu with his word: "Women are your field; go in unto them as ye will". He only struck half the blow. I say: go in unto them as ye will and they will. Two-thirds of modern misery springs from Woman's sexual dissatisfaction. A dissatisfied woman is a curse to herself and to everybody in her neighbourhood. Women must learn to let themselves enjoy without fear or shame, and both men and woman must be trained in the technique of sex. Sex-repression leads to neurosis, and is the cause of social unrest. Ignorance of sexual technique leads to disappointment, even where passion is free and unrestrained. Sex is not everything in life, any more than food is: but until people have got satisfaction of these natural hungers, it is useless to expect them to think of other things. This truth is vital to the statesman, now that women have some direct political power; they will certainly overthrow the Republic unless they obtain full sexual satisfaction. Also, women outnumber men; and one man cannot satisfy a woman unless he be skilful and diligent. The New Aeon will have a foundation of Happy Women: A Woman under Tabu is loathsome to Life, detested by her fellows, and wretched in herself.
The student should study in Liber Aleph and Liber 418, the connection between 'modesty' and the attitude of the "Black Brothers".