From Satan Service
In its etymological roots, the word 'satan' means 'adversary', and there are a number who take the term to heart in their pursuit of the 'Age of Satan' as a venue or period during which they feel compelled or privileged to engage parts of the cosmos, or everything in it, as an adversary to be challenged, opposed, vanquished, or destroyed.
The conventional origin for this term, like many things Satanic, is its Jewish and Christian scriptural context. In the story from the Jewish Tanakh and Christian Old Testament called 'Job', a wandering angel is called to assume the office of 'The Satan' to test the faithful to see how much loyalty to the chieftain deity truly lies under the surface while enjoying the milk and honey of proper alliance. In this instance, 'The Adversary' is a repeated, prodding, ordeal-maker, subjecting the character Job to loss and suffering the likes of which one would hope few would experience.
In the Christian New Testament the gospel character 'Satan' (now a proper name) purports to be able to offer up as temptation to Jesus rulership and dominion terrestrial. Christians interpret this as an adversarial act against the future Saviour, and the Satan as his enemy or adversary. The Messiah or Christos weathers the temptations by referring to the wisdom of Jewish elders, thenceforth depicted as fulfilling the prophecies of the messiah offered therein so as to bring conversion to the new faith.
Amongst Romantic poets, the Satan is lionized as an adversary of injustice and tyranny. Some Satanists draw on this, or duplicate the revision in their own manner. How it is done may take vitriolic and violent or passivist and neo-gnostic routes.