I wonder why St. Patrick chased the snakes out. They are a necessary part of our ecological balance.
As are, perhaps, the snakes of hell. Without evil to test us, we would not grow. So evil is a necessary part of our spiritual ecology.
The trick is to keep it within balance. Yes, the right word is ecological balance. An ecology or an Ireland that is overrun with snakes is toxic to other species of flora and fauna.
So if St. Patrick had not been drunk with green beer, he would have probably not chased all the snakes out of Ireland. But they didn't know of ecological balance then, did they?
Even our fearless hero Swedenborg talks of draining marshes and getting rid of frogs willy-nilly. I guess he did not know that if we drained all the marshes, killed off the bats and the toads, and planted lovely gardens with swans we would be unbalancing the environment - as we often do with the lovely green lawns of suburbia.