In Baptism in the Holy Spirit, Koo Dong Yun analyzes nine different theologians' constructs of Spirit baptism, also known as baptism of the Holy Spirit, as reflected from their various ecclesiastical and theological traditions (Roman Catholic, Lutheran, Dispensational, Pentecostal, and Reformed). This comparative study further underscores three distinctive features of Pentecostal theology: the Lukan orientation, the vitality of experience, and the verifiability of Spirit baptism.