This theoretical article approaches Christian religious denominations within which skeptical arguments with regard to vaccination and climate change are developed. These two types of skeptical positioning towards science are rooted in postmodernity, and manifest themselves as similar phenomena. Religion, as a social institution, fulfills the need for meaning, community, and responds to uncertainties generated by science developments. By conducting a thematic synthesis of previous literature, I identify analytical themes that capture the theoretical approaches on religiosity as a justification resource for vaccine hesitancy and climate change denial. These two types of science skepticism are supported and encouraged by some religious actors, who provide discursive resources anchored in interpretations of religious dogma. The knowledge deficit model, which is largely used for information campaigns on vaccination and climate change, impedes the understanding of the role of socio-cultural resources, such as religiosity, in popularizing science skepticism, and distorts knowledge of this social phenomenon. Understanding the social construction of skeptical positions towards science, as well as the institutional role of religion, contributes to better public communication on scientific topics. Despite religious arguments for vaccine refusal and exploitation of the natural environment, religiosity can also sustain pro-scientific views. Crises such as the COVID-19 pandemic and the climate crisis have the potential to provide avenues for transcending the religion vs. science antagonism, by involving religious leaders in promoting scientific information and scientific products, such as vaccination.