Rudolf Bultmann was one of the true giants of New Testament studies in the 20th century. A meaningful discussion of his work would fill several pages. While evangelicals disagree with him on fundamental aspects of his theology and hermeneutic, he did significant, useful work in the history of religions, form criticism, and exegesis. His commentary on John’s Gospel is particularly well known.
Progress in the past 50 years has made him less of a factor in current NT research, but in my opinion he still repays engagement and consideration. For all the weakness in his system, somehow Bultmann kept the proclamation of Christ as a crucial aspect of his belief. That by itself raises interesting issues to reflect on.
Lest we forget.