This article argues that how the United Nations (UN) conceptualizes legitimacy is not only a matter of legalism or power politics. The UN’s conception of legitimacy also utilizes concepts, language and symbolism from the religious realm. Understanding the entanglement between political and religious concepts and the ways of their verbalization at the agential level sheds light on how legitimacy became to be acknowledged as an integral part of the UN and how it changes. At the constitutional level, the article examines phrases and ‘verbal symbols’, enshrined in the Charter of the ‘secular church’ UN. They evoke intrinsic legitimacy claims based on religious concepts and discourse such as hope and salvation. At the agential level, the article illustrates how the Secretary-General verbalizes those abstract constitutional principles of legitimacy. Religious language and symbolism in the constitutional framework and agential practice of the UN does not necessarily produce an exclusive form of legitimacy. This article shows, however, that legitimacy as nested in the UN’s constitutional setting cannot exist without religious templates because they remain a matter of a ‘cultural frame’.