Read this: Wherever the Magisterial Reformation, which received support from the ruling authorities, took place, the result was a reformed national Protestant church envisioned to be a part of the whole invisible church, but disagreeing, in certain important points of doctrine and doctrine-linked practice, with what had until then been considered the normative reference point on such matters, namely the Papacy and central authority of the Roman Catholic Church. The Reformed churches thus believed in some form of Catholicity, founded on their doctrines of the five solas and a visible ecclesiastical organization based on the 14th and 15th century Conciliar movement, rejecting the papacy and papal infallibility in favor of ecumenical councils, but rejecting the latest ecumenical council, the Council of Trent. Religious unity therefore became not one of doctrine and identity but one of invisible character, wherein the unity was one of faith in Jesus Christ, not common identity, doctrine, belief, and collaborative action.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What type of character became central to religious unity in Reformed churches?
invisible