Abstract: This article analyses the role that the emic category of understanding plays in creating new forms of personhood and new worlds for sign language using deaf people in south India. As an ethnographic study of the production, dissemination, and circulation of Indian Sign Language Bible DVDs by an international non-denominational Christian missionary organization, this article analyses how the power of sign language as heart language lies in the potentiality of becoming a fluent signer and a member of a deaf sociality. Bringing the Anthropology of Christianity in conversation with the Anthropology of deafness/sign language studies, this article argues that anthropologists have ignored practices of verifying understanding in our interlocutors. In utilizing the concept of affective audits, this article analyses the practices by which understanding comes to take place. In addition, this article also argues that anthropologists must attend to how research on sensory formations might be presuming a ‘normal’ sensing body.