The answer lies in the legend surrounding his death. Helier lived the solitary life of a hermit on an offshore islet from which he could see Viking invaders in time to warn islanders to hide in a place of safety. One day a group of raiders caught Helier and beheaded him. Helier picked up his head and walked ashore.
His body was discovered on the beach still clutching his head in his hands, by a companion, Saint Romard. He placed the body in a boat and set off for the French mainland. The boat, guided by the hand of God, arrived at Bréville-sur-mer where a reputedly miraculous healing spring arose on the spot where Helier’s body rested overnight. A church was founded next to the spring, which is now topped by a statue and still attracts those seeking a cure.
From The Town of St Helier by Edmund Toulmin Nicolle
- "Saint Helerius was born at Tongres, the son of a Pagan. Early converted to Christianity he became a zealous missionary under Saint Marculf, whose name is intimately connected with the conversion of these Islands to Christianity. Many are the legends attached to the early life of St Helier. It is related how in early youth he was struck with paralysis and how Saint Cunibert cured him on condition that he should give himself up to GOd, how having grown to manhood he became a recluse and amused himself by gardening, but the hares got amongst his vegetables and made havoc thereof. So one day the Saint walked out with his cross in his hand and marked off a plot of his ground for the exclusive use of those wicked hares. Here he notified they might feast, beyond the limits they should respect his vegetables. No hare, it is related, ever over-stepped the boundary. But hares were liable to be hunted, and one day a bold sportsman leapt over the line of demarcation on horseback. As he leapt the fence a bough of a tree caught his eye and blinded him. He was now at the mercy of the Saint. The merciful Helerious made a sign with the cross and the eye was restored.
- "It was on the recommendation of Saint Marculf that Helerius visited Jersey. The population, it is said, only numbered then thirty souls. The Saint chose as his habitation, so the legend goes, a rock which was surrounded by the sea at high tide and communicated with the land by a natural causeway. There it is related he caused to be constructed the interesting cell which we know today as The Hermitage. SUch is the tradition handed down to us. The style of the masonry of this building and its nature hardly seem to belong to so ancient a period as that of the real Saint. It is more likely to be an oratory erected in memory of the martyred Saint at some later period in connection with the famous Abbey of St Helier.
- "Saint Helier gave himself up to his religious duties but the times were wicked. Sea rovers were abroad and unhappily they came to Jersey. As they were landing the Saint stretched out his hand and forthwith their ships were all blown out to sea. Then they fought against each other; but still enough were left to effect a landing and to decapitate poor Helerious. So the legend runs. After this begins the monkish history of his dead body, so mysterious that perhaps it is better not to attempt to unravel it.
- "Saint Marculf, we are told, in memory of this holy man founded a monastery near the Hermitage on the Islet, where Elizabeth Castle now stands, and in proximity to which was destined to congregate that population that had by then taken strong root in the soil and from which was to arise the Town of St Helier."