The article explores the linguistic methods employed in conveying the significant Christian invocation—a call for prayer—in Old English prose and poetry. This invocation finds its origins in Caedmon’s Hymn, the earliest known text of Old English poetry, which is notably unconventional. One of its distinctive features is the form of the call for prayer, highlighting the importance of comparing similar invocations in the broader context of Old English Christian literature genres. Research indicates that in homilies and commentaries on liturgical texts (such as the “Benedictine Office”), the call for prayer often incorporates modal words expressing duty or wish. Conversely, charms and certain poetic texts (such as the paraphrase of the Song of Three Youths in “Daniel”) utilize the imperative mood for the call for prayer. Notably, both “Caedmon’s Hymn” and the opening line of the poem “Genesis” employ modality of duty, aligning them with the genres of homily and commentaries. Thus, the linguistic methods employed in presenting the call for prayer are tailored to the communicative aim and genre of each text.