Leo Schaya [Sidi Abdul-Kuddus] (1916-1986), a member of the traditionalist school, is a significant researcher and author of the 20th century who carried out in-depth studies particularly on Islamic Sufism and Jewish mysticism. Born in Switzerland into a non-religious Jewish family, Leo develops a deep interest in Sufism to study Islamic mysticism following his encounter with Frithjof Schuon [Īsā Nūr al-Dīn] (1907-1998), a distinguished representative of Islamic spirituality in the West. He turns to Schuon, whom he values for his spiritual journey and sees as an experienced guide. He converts from his current religious belief and joins the Shadhiliyya order. As a result of his warm and visionary nature, during his travels, he gains knowledge about Islamic tradition and Sufism through his relationships with famous masters of Sufism such as Shaikh Muhammad at-Ta'dīl (d. 1371/1952) and Sufi thinkers like Titus Burckhardt [Sidi İbrahim] (1908-1984), who conducted theoretical studies on eastern doctrine. He perceives mystical teachings as a journey into the depths of the heart and soul in pursuit of a transcendent reality and truth. He sees them as a guide for human spiritual development and getting closer to Allah, representing the internal dimension of Islam. In his theory, overcoming the self or controlling ego-centered thoughts, the process of reaching divine love and truth, discovering one's true potential, killing one's self in this world of multiplicity to bring out the divine light within, and recognizing one's essence are all important. Furthermore, in the studies in which Schaya put his thoughts into writing, he associates certain Sufi concepts with other metaphysical principles and emphasizes the existence of a universal metaphysical understanding. The aim of this study is to analyze Leo Schaya's Sufi thought from a traditionalist perspective, to understand and evaluate the universal dimension he puts forward regarding Islamic tradition and mysticism. In other words, it is to investigate how Schaya's Sufi teachings provide guidance in the inner journey of humans and to delve into the universal dimension of his thoughts. For this purpose, document analysis, one of the qualitative research methods, has been used to examine the author's mystical teachings, and the data related to the subject has been collected. This data, categorized according to specific characteristics or themes, formed the general framework of the text. Schaya's inner teachings offer significant information on topics such as societal dynamics, spiritual interactions, and relationships between universal religious teachings. It is also seen that Schaya, rather than fully adopting the doctrines of traditionalist school pioneers, is in the effort to shape his own spiritual vision in an original way.