As social policies have changed to grant more rights to lesbian, gay, bisexual, and transgender (LGBT) individuals, some Christians in the United States have suggested that LGBT rights impede Christians' religious freedom. Across five studies, we examined the causes and consequences of zero-sum beliefs (ZSBs) about Christians and LGBT individuals. We demonstrate that Christians' beliefs about conflict with sexual minorities are shaped by their understandings of Christian values, social change, interpretation of the Bible, and in response to religious institutions. In Study 1, heterosexual cisgender Christians endorsed ZSBs more than other groups. Christians reported perceiving that anti-LGBT bias has decreased over time while anti-Christian bias has correspondingly increased. In Study 2, Christians' zero-sum beliefs increased after they reflected on religious values, suggesting that intergroup conflict is seen as being a function of Christian beliefs. Study 3 confirmed the role of symbolic threat in driving ZSBs; perceived conflict was accentuated when Christians read about a changing cultural climate in which Christians' influence is waning. An intervention using Biblical scripture to encourage acceptance successfully lowered zero-sum beliefs for mainline but not fundamentalist Christians (Study 4). A final field study examined how ZSBs predict sexual prejudice in response to changing group norms. After a special conference in which the United Methodist Church voted to restrict LGBT people from marriage and serving as clergy, zero-sum beliefs became a stronger predictor of sexual prejudice (Study 5). We discuss the implications of Christian/LGBT ZSBs for religious freedom legislation, attitudes toward sexual minorities, and intergroup conflict more generally. (PsycInfo Database Record (c) 2022 APA, all rights reserved).