In Christianity, the term was originally applied to a Christian who lives the heremitic life out of a religious conviction, namely the Desert Theology of the Old Testament (i.e., the forty years wandering in the desert that was meant to bring about a change of heart).
In the Christian tradition the eremitic life is an early form of monastic living that preceded the monastic life in the cenobium. The Rule of St Benedict (ch. 1) lists hermits among four kinds of monks. In the Roman Catholic Church, in addition to hermits who are members of religious institutes, contemporary Roman Catholic Church law (canon 603) recognizes also consecrated hermits under the direction of their diocesan bishop as members of the Consecrated Life ("consecrated diocesan hermits"). The same is true in many parts of the Anglican Communion, including the Episcopal Church in the United States, although in the canon law of the Episcopal Church they are referred to as "solitaries" rather than "hermits".
Often, both in religious and secular literature, the term "hermit" is also used loosely for any Christian living a secluded prayer-focused life, and sometimes interchangeably with anchorite / anchoress, recluse and "solitary". Other religions – for example Buddhism, Hinduism, Islam (Sufism) and Taoism – also have hermits in the sense of individuals living an ascetic form of life.
In modern colloquial usage, the term "hermit" denotes anyone living a life apart from the rest of society, or who simply does not participate in social events as much as is common, regardless of their motivation in doing so, including the misanthrope.
For the Hermit of Nilfeheim see Egill Skallagrimsson