He was a candidate in theology in 1956 and received his PhD in 1969 with a doctoral thesis on Zechariah 9-14. He was subsequently professor of Old Testament studies from 1970 to 1999, as well as dean twice (1975–77 and 1988–90). He has edited the Biblia Hebraica Quinta series, and a number of English encyclopedias and reference books, as well as the Hebrew Bible / Old Testament: A History of its Interpretation, (Göttingen).
Sæbø has also been active in revision of the Norwegian translation of the Bible, and contributed to the Norwegian Bible Society from 1965 to 1991.