In their recent article, Erbay et al considered whether a seriously injured patient should be able to refuse treatment if the refusal was based on a (mis)interpretation of religious doctrine. They argued that in such a case ‘what is important…is whether the teaching or philosophy used as a reference point has been in fact correctly perceived’ (p 653). If it has not been, they asserted that this eroded the patient's capacity to make an autonomous decision and that therefore, in such cases, it is the role of the healthcare professional (HCP) to ‘assist patients to think more clearly and rationally’ (p 653). There are, however, a number of problems with the reasons why Erbay et al suggest we should help patients to rationalise their decisions and how HCPs should go about this. In this article, the author explores some of their main arguments regarding consent and rationality (particularly in relation to religious beliefs), as well as Erbay et al's normative claim that HCPs have an obligation to promote autonomy by helping patients to come to a ‘rational’ decision. Ultimately, the author agrees that the (temporary) solution to the dilemma presented in this scenario (which was to insert an intravenous cannula into the patient in order to allow an infusion of fluids in the event that he changed his mind) seemed both pragmatic and ethically permissible. However, it is suggested that the arguments which underpin this conclusion in Erbay et al's article are largely unsound.