Research on the science of religions is often based on philosophical reductionism, whether materialism, biologism, or other preconceptions. This article intends to take religions seriously by starting from their point of view and not from the preconceptions of science, that is to say by doing “theoneuroscience” rather than “neurotheology”. This requires focusing at the outset on one religion. Christianity and particularly Catholicism is chosen. Christians explain their religion as a call to follow Jesus Christ. He placed at the center of his teaching the need to make moral choices. Therefore, understanding Christianity requires the study of moral choices, stages and levels of decision-making and their evaluation in comparison to God as an image. This will lead us to address the notions of the “dark night”, the “mount of faith” of John of the Cross and the “uncanny valley” of Masahiro Mori and to link them to theories of religion and data from neuroscience, in particular neuroimaging. We will propose that Christianity offers a means of evaluating moral choices through its doctrines of purification and image of God linked to a method of substitution: pleasure, suffering and compassion lead from the uncanny valley to a mountain of faith.