Since the early nineties, the author has been involved in the Sufi path of Hazrat Inayat Khan and Murshid Samuel Lewis. These Sufi teachers inspired him and his partner Ariënne to undertake a study in the different world religions to deepen their understanding in the Unity of religious Ideals. This led to Unity and Diversity, a primer in the world religions and Wali's first book in English.

The centennial of the Universal Worship, an interfaith ritual from Hazrat Inayat Khan celebrating the main spiritual traditions of the world, inspired Wali & Ariënne to revisit these traditions in meditation sessions of one hour in the style of their Sufi morning practices, so working with chant and movement, with breath and silence. A recorded version of these sessions is available through the author's website. The second part of this present book offers the background to these recordings, diving deeper in the Universal Worship, the Upanishads, the teachings of Lord Buddha, the Jewish teachings around the soul, the Christian Mass and Sufi zikr. In the first part, the author deepens subjects such as mantras, the fine line between belief and superstition, and the art of meditation.