Some reviewers, such as Wayne Hammond, have noted the novel's apparent preoccupation with sexual love.

The book does, after all, contain descriptions of bare breasts, interspecies marriage (between humans and nephilim), and attempted seductions. Hammond argues, however, that L'Engle handles these elements with propriety.

Certainly, the novel posits a mature, spiritual love (like that of Shem and Elisheba, Japeth and Oholibamah, and the twins' parents) as the ideal. It is at least partly for this reason that the twins realize that Yalith cannot return home with them and that, as is suggested in the title of Chapter 11, "many waters cannot quench love."

Like many of L'Engle's novels, particularly A Swiftly Titling Planet, Many Waters comments on contemporary society, including social and environmental issues. The seraph, Alarid', it turns out, is familiar with the late twentieth century and reminds Dennys that he comes from a time of...