Tears reflect strong emotions in those who shed them and in those who witness them. Researchers (e.g., Judith Kay Nelson and Ad Vingerhoets) understand weeping as an attachment behavior, or a behavior directed toward another person that seeks to reinforce relationship and elicit caregiving. This understanding of weeping coheres with decades of research in attachment theory (initiated by John Bowlby) and more recent work in the social sharing of emotions (by Bernard Rimé et al.). Crying is not a solitary behavior that discharges emotion, but a social behavior that builds relationship and facilitates the co-regulation of emotion. This modern theory of weeping illuminates ancient literary texts that employ weeping as a motif for diverse purposes. The present paper will focus on weeping in ancient prayer texts. It is a corpus-based study that examines the motif of weeping in large collections of Hebrew and Akkadian prayers in order to discern both specific functions of weeping in prayers and larger patterns in the distribution of the motif. The textual evidence of ancient prayers tends to confirm findings in the psychology of religion that persons at prayer engage in an attempt to regulate their emotions through relationship with a deity that closely resembles how people regulate emotions in relationships with other humans. In prayer texts, the speaker may verbalize non-verbal weeping behavior in order to draw on the power of tears to elicit caregiving and connect to the deity.