The author writes: 'If someone asked me to tell them all about the Holy Spirit, and if they had time to listen, this book tells what I would say. Here will be found what the Catholic Church and tradition have held about the Holy Spirit, in simple language which aims to be both enlightening and uplifting... I have often in the past written about God the Father and about Jesus; so it seemed to be high time to write about the Spirit who brings God's love to us, and who takes our love back to God. An unusual feature of this book is the attention paid to the phrase from the Creed: ..". who proceeds from the Father and from the Son." What seems to first to be mere words turns out to a key to spiritual freedom, reappearing in many areas of our faith and Christian life.'

Gerald O'Mahony was born in Wigan, Lancashire. He joined the Society of Jesus at the age of 18, and was ordained priest at age 30. He was a school teacher for four years, before being invited to join the team of advisers in religious education for the Archdiocese of Liverpool. Ten years on he joined another team, as retreat giver and writer in Loyola Hall Jesuit Spirituality Centre near Liverpool, where he has lived and worked happily ever since.