While Christians take a variety of stances on contraception today, this diversity of opinion and practice is a relatively recent historical development. The majority report in Christian history has been overwhelmingly vocal in its opposition to birth control. The Early Church fathers condemned the use of contraception, leaning heavily on the negative example of Onan in Genesis 38 as evidence for their position and arguing that procreation was the primary purpose of sexual intimacy. This same basic stance was reiterated and reinforced by the Medieval monks and theologians. Even with the sweeping changes which the Reformation brought to Christians’ views of marriage and family, leading Reformers (such as Luther and Calvin) maintained the church’s historic opposition to contraception. Up through the 19th century, both Protestant denominations and the Roman Catholic church stood united in their condemnation of contraception. The first official break with this view came with the 1930 Lambeth Conference, in which the Anglican Communion cautiously opened the door for Christian use of contraception. Within a few decades, the Christian consensus on contraception had collapsed and a range of attitudes and approaches towards contraception began to develop (Ben Franks).