Matthew uses omicron lambda iota gamma o pi iota sigma tau omicron sigma to critique inadequate faith from the disciples, adapting already linked Markan pericopes to create a set with a distinct rhetorical function. For the Gospel audience, these function together to call people to the sort of wholehearted trust exemplified in the first use of the term (6,25-34), while developing this ideal in a christological direction. Linguistic studies on the role of the vocative highlight how omicron lambda iota gamma o pi iota sigma tau omicron sigma is used to effect this goal, as it serves to recharacterize the disciples, drawing attention to the narrative frame, and emphasising the imperative force of Jesus' rhetorical questions.