St. Teresa of Jesus (1515-1582) is not known to be a philosopher and yet we can derive many important philosophical insights from her work. Proof of this is the existence of studies and dissertations from the philosophical perspective dedicated to her thought. More than this, St. Teresa de Jesus, Doctor of the Church and acknowledged Mistress of Spirituality, proposes a way of understanding philosophy, or love of wisdom, by being a spirituality or a way of living for one to become Spirit. The present work focuses on the notion of Truth, hence the title 'Spirituality of Truth," parting especially from Teresa's reflections on this regard in her Book of Life, 40. The result is a renewed comprehension on the love of wisdom going beyond a purely rational understanding of the same into something more experiential and dynamic.