He was also a graduate of Western Theological Seminary and received degrees of D.D.
[1] One of Ketler's early teachers was Joseph Newton Pew who later went on to build a fortune in the oil industry.
Ketler served as President of Grove City College for 37 years from 1876 to 1913.
Under Ketler's leadership: "[b]y the turn of the century, the enrollment had grown to 660 students, the faculty was enlarged to 20 members and the campus had increased to 40 acres with four substantial buildings.
"[2] His son Weir Ketler later served as president of the college.