Criteria for inclusion is:
(1) Has made a recognizable contribution to NT scholarship and (2) their works either have or shall endure the test of time. These include authors who are my favourites and one's that I think are influential (at least upon me).
25. Richard Hays
His book The Moral Vision of the New Testament is a classic. Similarly his work on narrative theology and his championing of the subjective genitive reading of pistis christou warrant a ranking. His 1 Corinthians commentary also challenges the consensus of a realized eschatology at Corinth (instead the problem was not enough eschatology).
24. Adolf Schlatter
Underrated German scholar who wrote some good NT Theology books (only now available in English). Apparently memorized the entire Gk NT and TDNT was dedicated to him!
23. G. Bornkamm
His book Jesus of Nazareth is the best of the 2nd Quest. His book on Paul is quite disappointing, however, he did pave the way for work on redaction criticism in Matthew.
22. T.W. Manson
British scholar who worked mainly on the Gospels and the Jesus Tradition and produced several notable works like The Sayings of Jesus.
21. I. Howard Marshall
Still a sharp evangelical scholar known mainly for his commentaries on Luke-Acts, Johannine Epistles, Thessalonians and also the Pastorals. Various other studies on the atonement, perseverance, biblical interpretation guarantee his legacy.
20. Gerd Theissen
In hindsight, leaving him out was a mistake. Works on sociology on the NT were significant, I have enjoyed his studies on the historical Jesus in particular.
19. Joseph Fitzmyer
Catholic scholar who has made contributions to study of the DSS, Paul (Romans commentary; Pauline Theology) and especially Luke-Acts.
18. Hans Conzelmann
His work on Luke changed the course of study and impacted ideas of Christian eschatology.
17. F.F. Bruce
Commentaries on Acts (English and Greek text) are still models of scholarship and how philology, Archaeology, theology and history all go together. Bruce was the pioneer evangelical NT scholar. My college, Highland Theological College, has even named a lecture series after him. His New Testament History is still the best NT history book around in my view (over Barnett and Witherington). So many smaller books as well which made scholarship accessible to lay people (watch out - I might send him up the list later).
16. Raymond E. Brown
One of the finest Catholic scholars of his generation. His work on Johannine materials is well known. More importantly his massive works: Birth of the Messiah and Death of the Messiah are classics.
15. Richard Bauckham
I like anything this guy writes. He has that uncanny ability to take stock standard assumptions of scholarship and show how tenuous they are. At the moment I'm closing reading his Gospel for All Christians and continue to be impressed. His various articles on eye-witnesses and the Gospel tradition, parting of the ways, Son of God, etc. are all worth reading and frequently cited. Studies in Revelation are classics for that area of study. One scholar I could handle be stranded on an Island with.
14. Joachim Jeremias
German scholar who was doing serious Jesus study when it wasn't fashionable any more. His views of Aramaic are a bit antiquated now, but his work on the parables, eucharistic words of Jesus, NT Theology are classics. I spent my Ph.D thesis trying to refute his book Jesus' Promise to the Nations. Both a learned and pious man.
13. C.H. Dodd
One of the great 'Chucks' of British scholarship (with Barrett and Moule). His realized eschatology was a corrective to Schweitzer/Weiss (though he went too far), his work on the parables is memorable as his work on tradition and interpretation in the fourth Gospel. Other books on the Apostolic message and Jesus as the Founder of Christianity are good reading. There is a limerick about him too:
There once was a man called Dodd
Who had a name that was exceedingly odd
He spelt, if you please,
His name with three D's
When one is sufficietn for God
12. C.K. Barrett
What can I say, commentaries on John, Romans and 1 Corinthians are still worth looking at today. Other stuff on the Jesus Tradition in the Gospels and the Holy Spirit in the Gospels worthwhile too. His Acts ICC commentary is the standard for commentary writing and he has some useful small books on Paul and other NT Themes
11. Ernst Kasemann
Iconoclast German scholar who was of the Bultmannian school, but still his own man. He single handed re-initiated the 2d Quest for the Historical Jesus (in Germany anyway), interesting interpretation of the "Righteousness of God", a great Romans commentary and his dispute with Stendahl is classic.
10. Martin Hengel
My favourite German scholar. His works on the Gospel of Mark, Judaism, Zealots, Historical Jesus, Paul, Septuagint etc, all good stuff.
9. James D. G. Dunn
Starting in the 70s Dunn was writing good stuff on the Holy Spirit, then he moved to Paul and was part of the vanguard of the New Perspective. Works on Christology, the Parting of the Ways, Pauline Theology, the Unity and Diversity of NT, and now a massive 'Christianity in the Making' project. Must meet this guy some day.
8. N.T. Wright
Probably todays leading evangelical scholar - his early work on Paul (Climax of the Covenant, Colossians) are good reads. His Christian Origins and the Question of God series changed the way I think about the NT, Jesus and God.
7. E.P. Sanders & Albert Scweitzer
I declare number 7 a draw!
Sanders' work on Paul, Jesus and Judaism makes him one of the most influential scholars of the last 30 years. At the root of Sanders I think was Schweitzer, and the Old missionary doctor himself deserves a place in the top 10 (my oversight) given his works on Jesus and Paul.
6. Rudolf Bultmann
Major works on Diatribe in Romans, History of the Synoptic Tradition, NT Theology, commentaries on John and 2 Corinthians, major studies on theology too. (Though I still think that he was primarily an existentialist and NT was just his medium).
5. F.C. Baur
The Father of modern NT study, his work on Paul set the benchmark of study, particularly his analysis of Galatians.
Early Church Father was a master of language, and erudite. Don't let his allegorizing put you off, he still knew how to wrestle with the text.
3. John Calvin
Though primarily a systematic theologian, Calvin still composed superb and timeless commentaries on nearly everybook of the NT except Revelation because, he said, 'I donnot understand it'.
2. J.B. Lightfoot
The Old Master himself, treat on textual criticism, his paraphrases of NT passages in Colossians and Galatians are still excellent to cite in Sermons. Translations of the Apostolic Fathers too.
1. Martin Luther
'Exegesis is learned from the Masters' says Stephen Westerholm and he correctly had Luther in mind. His discovery of the 'righteousness of God' changed the course of history.
And in the words of the great American philosopher, Forrest Gump, that's all I have to say about that.