JACK REUMANN was not the kind of teacher who would take his students out for a beer after a tough seminar on deep subjects. But he'd buy them ice cream.

"Jack loved ice cream," said a former student of Reu- mann's at the Lutheran Theological Seminary in Philadelphia.

Jack Reumann also loved exploring and explicating esoteric theological issues, which he pursued with a dedicated passion for 45 years as a teacher.

He had a knack for translating difficult questions of church and biblical material into simple and easily understood language that stunned his colleagues.

"Jack Reumann had the incredible knack - better than anyone I ever saw - of listening to the comments of others and then putting out a crisp, concise motion or recommendation for action that would have people saying, 'Yes, that's what we are trying to say,' " said the Rev. Dr. Edgar R. Trexler, former editor of The Lutheran Magazine.

"He was so careful in his use of language and its nuances in getting dead-on to the heart of the matter."

The Rev. Dr. John H.P. Reu-mann, a New Testament professor who had an encyclopedic knowledge of the Bible and whose influence ranged from the seminary classroom to national and international ecumenical and interfaith circles, died Friday. He was 81 and lived in Lafayette Hill.

"He had many gifts and a rare breadth of knowledge about the Bible and theology, but more than that, he was an excellent citizen of the church," said the Rev. Dr. LeRoy Aden, retired professor of pastoral theology at the seminary.

It was not easy being a student of Jack Reumann.

"When he lectured, you felt you had to buckle up and hang on to what he was saying," said the Rev. Peter Bredlau, chaplain of Muhlenberg College and one of Jack's last students before he retired in 1996.

"Yet he was a truly generous spirit," Bredlau said. "He would never use his intellect to embarrass you."

The Rev. Dr. Philip D.W. Krey, seminary president, called Reu-mann "a giant in the faith."

"Dr. Reumann was a model in every respect for many of us who have followed him at the seminary and in the church," Krey said.

Among Jack Reumann's special interests were research on the life of Jesus and the origins of Christianity, especially the Apostle Paul, ecumenics and Lutheran-Roman Catholic dialogues.

One of his major accomplishments, apart from his teaching, was his role in shaping the "Joint Declaration of Justification," adopted in 1999 in Augsburg, Germany, by leaders of the Lutheran and Roman Catholic churches.

The declaration was designed to answer issues that have divided the two churches since the Reformation in the 16th century.

Jack Reumann was born in Easton and grew up in Lansdale. He graduated summa cum laude from Muhlenberg College in 1947. He received a master's degree in sacred theology from the Lutheran seminary in 1951, a master's in the classics from the University of Pennsylvania in 1950, and a Ph.D. in classics and Semitic studies from Penn in 1957.

He was ordained in 1950. Over the years, he studied and taught in Cambridge and Oxford, England; Goettingen, Germany; Bangalore, India; and Jerusalem.

He and his wife, the former Martha Weber Brobst, whom he married in 1958, were particularly interested in welcoming and supporting international students at the seminary.

Jack was an avid Phillies fan and had an encyclopedic knowledge of baseball.

Besides his wife, he is survived by three daughters, Rebecca Jane Reumann-Moore, Amy Elizabeth Reumann and Miriam Reumann Sadler, and three grandchildren.

Services: 2 p.m. today at Trinity Evangelical Lutheran Church, 1000 W. Main St., Lansdale.

Donations may be made to the Faculty Chair in Bible, Lutheran Theological Seminary, 7301 Germantown Ave., Philadelphia 19119, or Christ Ascension Lutheran Church, 8300 Germantown Ave., Philadelphia 19128. *