Habermas' view that contemporary philosophy and social theory can learn from religious traditions calls for closer consideration. He is correct to hold that religious traditions constitute a reservoir of potentially important meanings that can be critically appropriated without emptying them of their motivating and inspirational power. However, contrary to what he implies, his theory allows for learning from religion only to a very limited degree. This is due to two core elements of his conceptual framework, both of which are key features of his account of postmetaphysical thinking. The first is the requirement of ethical agnosticism; this requires philosophy and social theory to refrain from offering guidance on questions of the good life. The second is his language-immanent conception of truth in the domain of practical reason; this follows from his rejection of any source of validity beyond human communication in this domain. I make the case for a more robust account of learning from religious traditions and metaphysical worldviews, arguing that for this purpose Habermas must modify his requirement of ethical agnosticism and relinquish his language-immanent conception of truth.