The tension between religion and science as a long-standing barrier to science education has led researchers to explore ways of improving the experiences of Christian students in biology who can experience their Christianity as stigmatized in academic biology environments. As undergraduate science classes become student-centered, interactions among students increase, and Christians may feel a need to conceal their religious identities during peer discussions. In this interview study, we used the social psychology framework of concealable stigmatized identities to explore 30 Christian students' experiences during peer interactions in undergraduate biology courses to find potential ways to improve those experiences. We found that students felt their religious identity was salient during peer interactions in biology, and students thought revealing their religious identity to peers in their biology courses could be beneficial, yet few actually did so. Additionally, though most students "anticipated" stigma, comparatively few had "experienced" stigma from other students in their biology courses, despite the prior documented cultural stigma against Christians in biology. These results indicate a need for future studies exploring the impact of learning environments in which students are given the opportunity to share their religious identities with one another, which could reduce their anticipated and perceived stigma.