Richard Bellingham, 57, of Wilmington, was arrested on Thursday and charged with Indecent Assault and Corruption of Minors.
Police say one of the victims, now 39 years old, contacted state police in Media, Pa. to say, as a child, she had been sexually assaulted by Bellingham.
As the investigation continued, police say they learned of three more victims who were allegedly molested by Bellingham when they were between four and 15 years old.
Bellingham, and the victims, were affiliated with the Church of Our Saviour which operated in Concord Township, Delaware County, from the 1970's until 2004, according to investigators.
The sexual assaults occurred in various different locations throughout Delaware County, Pennsylvania as well as in neighboring states of New Jersey, Delaware, and Maryland, police said.
Bellingham was arraigned on Thursday and bail was set at $100,000 cash.
Anyone with information on BELLINGHAM is asked to contact Trooper Jon Sunderlin, Pennsylvania State Police, Criminal Investigation Unit, at 484-840-1000.