Wilhelm Rittenhouse, a native of Mulheim in the German Principality of Broich, settled in Arnheim, Gelderland, The Netherlands and learned the papermaking trade from his brother-in-law. He went to New Netherland about 1688, but chose settled near Germantown, PA. There Wilhelm built the first paper mill in colonial America about 1690.
Wilhelm followed the Mennonite faith. He was the first Mennonite pastor in Germantown, and in 1701 was established as the first Mennonite Bishop in America. The ministers in Altona, Germany were reluctant to make the trip to America to ordain Rittenhouse and suggested that the local congregation ordain him. Before the situation could be resolved, Wilhelm died in 1708.
Eldest son, Claus, followed his father as a Mennonite minister and paper maker. Garrett, who was a farmer and grist miller, probably followed the faith as well. Garrett's eldest son, William, moved to Hunterdon Co., NJ. He married into the Howell family, who were members of the Church of England. William's son, Isaac. married into the Baker family, which was probably Church of England.
Did William and Isaac continue the Mennonite beliefs of Wilhelm? Probably not. Did they join the Church of England? Perhaps. By the time of the American Revolution, the Church of England [Anglican] was a target of local patriots. My guess? They probably joined the local Presbyterian Church. Isaac's daughter, Elizabeth Prall was a member.