In this essay, the author tries to shed light on the cultural roots of the Hungarian saying 'az apostolok lován megy' (to go on foot; lit. to ride the apostles' horse). Expressions of biblical origin make up a considerable part of the vocabulary of each European nation (e.g. the number of these idiomatic expressions in Hungarian exceeds 1 000). Since these idioms first spread by word of mouth, and were written down only later, they are known in several variants. Many of the parables of the New Testament can be traced back to pre-biblical times (e.g. in Philo's and Origenes's works). The first Hungarian collection of proverbs (1596) already contained sayings that were of biblical origin. After giving a typology of biblical phrases, the author analyses the word 'apostol' and its usage in phraseology, comparing it with biblical texts as well as similar expressions in other languages. All this is needed for the sake of a thorough structural study of 'az apostolok lován' and its equivalents. The sayings of the European languages are, on the whole, divided according to the various language families. Peoples speaking Romance languages and sharing a common territory, believe that it is either the apostle, the saint or the monk who rides the horse; whereas, the speakers in the Balkans travel as apostles, because they borrowed the expression from the Greek. On the basis of the data collected, it looks almost certain that the Hungarian expression (first used in 1792) comes from the German. The idiom is of Germanic origin in Czech and Finnish as well. Medieval Latin 'per pedes apostolorum' (lit. on the apostles' foot) used all over Europe, has no derivative in any European language.