The green snake/white snake story apparently has been filmed more than once (though I suspect this one is the best) and is shown in Taiwan (and elsewhere?) around Dragon Boat Festival time; but I don't know why. The emphasis is usually on White Snake, though.

The way I saw it, it's about the basic inhumanity of the Taoist monk, who's great magical powers are matched only by his ego, his weakness for the female form, and his fundamentalist-like zeal to make sure everyone else is acting the way they're supposed to, even while his own faults go uncorrected. In this age, with fundamentalists of the major religions becoming more and more vocal and assertive, maybe this cautionary tale should have wider circulation.

The monk and Green Snake are similar in the sense that they are both struggling with their sexual passion; the monk to eliminate it and Green Snake to experience it. But through their struggles, non-human Green Snake learns what it means to love and exercise compassion for others, while the Taoist apparently doesn't learn anything and his actions result in increasing destruction.

The movie doesn't present a very flattering picture of monks, but I took it as an exaggeration to make a point.

The movie has its faults, but overall its very well done, well-acted, and recommended.