Greetings Blackcat!
I cannot speak for the members of the Golden Dawn as I am not alffiliated with them...but from a Solomonic viewpoint and one that also uses Khemetic ritual there are a variety of purification 'rituals' that may be employed. Your need for a physical purification series is interesting....most all purifying ritual used are based on Theurgy of some sort. Where it could be argued that Chaos magicians and or Thaumaturges wouldn't necessarily adopt a theurgic venue. I leave it to your interpretation with your own spiritual views and what you might consider 'pure'.
The Lustral Bath uses basic sea water or an herbal decoction that has been 'blessed' to leech away the toxins, poisons and 'imprities'. In Khemetic Ritual it is the idea of and act of becoming physically clean with intent before entering into Heka/magical ritual. Again, Theurgy plays a role (as well as the more practical side of things). There are definate electro-chemical effects brought about with salt water or running water or...etc. Physics can and does play a part in Magic!
Fasting from eating certain foods. The ingestion of food prior to ritual is said to 'close down' certain psychic centers/chakras, therefore the abstinence of eating for at least 3 hours before any operation. Certain foodstuffs that are forbidden or taboo are avoided for upwards of days to weeks beforehand...Theurgy rears its head again. Pragmatists recognize that this isn't necessary but results bear out ...it depends on just what you wish to do!
Abstinence from sex....the biggie for most younger practioners (LOL, at my age, ...eh?) Sex excites energy flow in different parts of ther body and brain. These 'currents' may prove deleterious to the working. Then, if the ritual is to involve Sex then you might just want to build the tension beforehand.
Purification will be dictated by ones beliefs and/or needs and/or outlook/personal philosophy. I am first and foremost a pragmatist but...I found myself practicing certain forms of purification dictated by Theurgic influences. Part of me is very disappointed in myself for this. *sigh* I'll get over it. I hope that you will too! My articulation leaves much to be desired. Good Luck! (IMG:
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