In 1963 the party finally entered the House of Representatives in the person of Pieter Jongeling, who was made top candidate on advice of prominent professor of theology J. Kamphuis. In the 1967 general elections they were able to retain their one seat. During the early 1970s a group called Nationaal Evanglisch Verbond (NEV) had left the ARP because they thought the party's alliance with the Catholic People's Party was wrong. They asked the board of the GPV whether they could join their party. This was rejected by the board of the GPV, who said that the party was open only to members of the liberated Reformed Church. This group would later become the Reformatory Political Federation (RPF). In the 1971 general election the party was able to obtain a second seat, which it managed to retain in 1972. In the 1977 general election Jongeling was replaced by Verbrugh and the party lost one seat. Before the 1981 general election, Verbrugh was replaced by Schutte, who would lead the party until 2001. He was able to retain the one seat in 1981, 1982 and 1986 general elections, and he won a second seat in 1989. In the 1994 genera; election the party retained its two seats. In 1993 the GPV officially opened itself to non-liberated members. This started a slow process of cooperation between the GPV and the RPF, another orthodox Protestant party. From the 1998 general election onwards, the two parliamentary parties began to cooperate, holding common meanings and appointing common spokespersons. The fact that the GPV had only two seats and the RPF three inhibited the cooperation. In 1999 their parliamentary parties in the Senate officially merged, forming one parliamentary party. In 2001 the same happened in the House of Representatives. In 2002 general election the GPV and RPF presented a common electoral list of candidates for the House of Representatives, entering the elections as the Christian Union: they obtained four seats. In 2003 the GPV officially disbanded, making its merger into the Christian Union final.
