Although his mother remained a teacher in New Haven, Kentucky for her whole career, his father turned to jobs that brought more income, including waiter, shopkeeper, and shipyard laborer.

"[4][5] Hardin's first assignment as a priest was as assistant treasurer at St. Meinrad; he completed studies in business at the University of Notre Dame to prepare him for this role.

He quickly became involved in protests opposing police brutality, segregation, poverty, and the construction of a highway, Interstate 65, that threatened to cut the neighborhood surrounding Holy Angels in two.

[1] When the existing prelate of the Archdiocese of Indianapolis, Archbishop Paul Schulte, was pressured to silence Father Hardin, he ordered him to return to St. Meinrad.

Holy Angels parishioners and other supporters responded by staging a walkout during the Easter Sunday services conducted by Archbishop Schulte in Saints Peter & Paul Cathedral on April 6, 1969.

[1][11][12] The Archbishop subsequently rescinded his order, but Father Hardin decided that he could no longer serve effectively and resigned his post at Holy Angels in December 1969 to found the Martin Center.

[1] To raise funds for the Martin Center, Father Hardin served as a consultant with major corporations, school systems, and others on race relations training.

As he traveled and brought in income, Sister Jane managed the programs that Martin Center offered to the local community on African American history and culture, race relations, and other topics.

[15] In 1971, Father Hardin and Dr. Raymond Pierce received a grant to establish the Sickle Cell Center to test for the disease and to educate families.

[21] As Father Hardin became increasingly concerned about the lack of good higher educational options for African-American adults in the community, he developed plans to establish a university.

"[23] As Martin Center College increased in size and reputation and moved in 1987 to a larger campus on the east side of Indianapolis, Father Hardin was recognized as a key educational leader.

[27] Although he planned to write several books following his 2007 retirement, Father Hardin was troubled by turmoil that ensued at Martin University with the advent of his successor, who made rapid changes.