If wanderers ask you, “What are the prerequisites for the development of the wings to self-awakening?” you should answer, … “a monk has admirable people as friends, companions and colleagues. This is the first prerequisite for the development of the wings to self-awakening.”
     — Buddha, Anguttara Nikaya 9.1

Spiritual friendship is central to contemplative spirituality — especially in an interfaith group, forming bonds of community where there is no common foundation in doctrine, religious language or heritage.

In the contemplative branches of the world religions, friendship is frequently cited as an essential source of support, empowerment and accountability along the spiritual path. Buddhism sees kalyanamitra, or “admirable friends”, as essential to progress on the journey to enlightenment. Sufi poetry exudes friendly sentiments. And in Christianity, similar value is placed upon koinonia — a Greek word for how the Holy Spirit flows through the fellowship, communion and participation of the gathered community.

Spiritual friendship is also a key aspect of spiritual direction, which is often called “soul friendship” or “spiritual companionship” — such as in the Celtic tradition of valuing the anam chara, or soul friend.

Spiritual friendship is part of what makes a religious community a true community, a true sangha, and not just a bunch of people.

A key question is, “how is this type of ‘spiritual’ friendship different from ‘ordinary’ friendship?”