From the earliest days of Christianity the cross was believed to be a most potent protective symbol against fairies and all evil spirits. It is even possible that cross-roads had a pre-Christian significance, as sacred to the god of limits and a place of sacrifice. The cross in all its forms was protective — the 'saining' or crossing of one's own body or that of another, a cross scratched on the ground or formed by four roads meeting, a cross of wood, stone or metal set up by the roadside, a cross worn as a trinket round the neck, all these were believed to give substantial protection against devils, ghosts or fairies. Sometimes this protection was reinforced by carrying a cross of a particular material — of rowan wood, for instance, for this wood was a protection of itself — or for trinkets crosses of coral or amber, both of some potency.

An example of the efficacy of 'saining' as a means of rescuing a captive in fairyland is to be found in Walter Scott's 'Alice Brand', a ballad from The Lady of the Lake:

But wist I of a woman bold,

Who thrice my brows durst sign,

I might regain my mortal mould,

As fair a form as thine.