Growing recognition of the benefits of contemplative practice for the reduction of harmful stress and the improvement of prosocial behavior is prompting research into how these effects arise. We define contemplative practice as intentionally attempting to suspend all discursive and evaluative thought. In practice, most forms of contemplative practice emphasize compassion for self and others, as well as humility and emotional equanimity. Given these strongly social and emotional emphases, we hypothesized that contemplative practice involves reorganization of social and emotional processing in the brain. To better understand the effects of contemplative practice, then, we took an approach based in social and affective neuroscience. We worked with participants who adhere to a version of Christian contemplative practice known as Centering Prayer. Centering Prayer is a widely practiced form of Christian contemplation, with more than 15 groups based within the Los Angeles. Using functional magnetic resonance imaging (fMRI), we studied the effects of Centering Prayer on 1) neural networks involved in making decisions about how trustworthy other people are and 2) neural networks involved in meta-awareness during contemplation. In relation to meta-awareness, we found an activation of prefrontal cortex when participants reported returning to the practice after becoming aware of mind-wandering (i.e., following discursive thought). This activation was absent in a non-meditative control task assessing meta-awareness. In relation to social decision-making (i.e., trustworthiness judgments), participants engaged in either 10 minutes of practice or 10 minutes of a non-meditative, attention-demanding task, followed by a task in which they had to decide the trustworthiness of people from faces alone. We found that 10 minutes of Centering Prayer, but not the control task, was associated with activation in the amygdala and right prefrontal cortex during trustworthiness judgments. The region of prefrontal cortex overlapped with the region activated during actual practice of Centering Prayer.