In the hieratic Egyptian mathematical texts, which are extant from the periods of the Middle Kingdom and the Second Intermediate Period, the verb form sDm.xr.f has its most numerous attestations. This verb form has been recognized to express a necessary consequence from a previously stated situation, e.g. in indicating the result of a previously stated arithmetic operation. Therefore one might expect this form to be similarly (frequently) used in Egyptian laws to express the consequences of wrongdoing. Only few collections of laws from pharaonic times are extant, of which the earliest are the Great Edict of Haremhab and the Nauri Decree of Sethos I. both from the beginning of the Ramesside Period. These sources, however, show no use of this form. In this respect then, the Egyptian concept of rational practice is different from its Mesopotamian neighbour, where a connection between mathematical and legal procedure texts has been shown by Jim Ritter based on their verbal structure. Using examples from several Egyptian genres of texts, I would like to document that in ancient Egypt, too, this relation existed, and explore how it was expressed.