This essay examines the image of the Eucharist in the poetry of the Peruvian writer César Vallejo (1892-1938). I argue that unlike his modernista forebears, Vallejo regularly employs the Eucharist not as an image of the ecstasy of sexual union, but instead as an image of guilt, melancholy, frustration, and loss. In one sense, such images can be read as deliberately blasphemous distortions of the Christian picture of the Eucharist Vallejo imbibed as a child. My central thesis, however, will be that the same images can also be read, perhaps in part against Vallejo's own intentions, not as distortions of the Eucharist but as offering insights into the nature of the sacrament itself. I develop this thesis in two parts. First, I argue that despite the centrality to eucharistic theology of the themes of communion, spiritual intimacy, and “real presence”—themes that made it an almost irresistible poetic symbol of sexual desire—the Eucharist itself is also and fundamentally a sacrament of absence, delay, and failure. Second, I suggest that by drawing, however implicitly, on these latent elements of eucharistic theology, Vallejo's poetry opens up a space to think about certain aspects of the sacrament which the modernistas’ erotic exuberance tended systematically to obscure.