Abstract: Religious experience in First Corinthians 12 and 14 is a neglected dimension in New Testament studies. An example of this neglect appears in a recent commentary on First Corinthians by Anthony Thiselton (The First Epistle to the Corinthians) who suggests that 'it goes against the grain of Paul's emphasis in the thanksgiving...to focus attention on the 'religious experience' of 1 Corinthians 12-14.' This thesis offers a challenge to Thiselton's statement and will attempt a new analysis of First Corinthians 12 and 14 in the light of religious experience. By religious experience is meant those experiences that bring persons into contact with the 'other' world of spirit. The historical-critical method and philological analysis will be used to understand the text and illuminate the religious experience found there. Particular attention will focus on the use of the term pneuma, both in the singular and plural, as an expression for the Corinthians' experiences with the spirit world, especially with regard to the verbal communication of spirits through mediums, i.e., prophecy and glossolalia. The insights of scholars such as Hermann Gunkel, Heinrich Weinel, James D. G. Dunn, John Levison, and Luke Timothy Johnson will serve as a scholarly basis from which to study religious experience in First Corinthians 12 and 14. Texts from Plutarch, Josephus, Philo, and Pseudo-Philo will serve as historical witnesses contemporary with Paul to the activities of good spirits possessing persons and speaking through them by use of the vocal chords. The term 'spiritism' is almost always used in a negative sense in English Bible versions to denote the condemnation by God of communication with spirits of the dead or spirits of divination. This thesis will argue that spiritism is as ambiguous as the Greek noun pneuma upon which the term 'spiritism' is based. Spiritism denotes any spirit, good or evil, human or otherwise. A holy spirit and a spirit of God fall within this range. First Corinthians 12 and 14 is not so much about 'spiritual gifts' as it is about 'spiritism' or 'communication with the spirit world.'