<p>In the recent paper entitled “The relics of Jesus and Eucharistic miracles: scientific analysis of shared AB blood type” the issue was raised that assignment of AB blood type using serological methods with such articles may be difficult due to the shared nature of AB antigens between humans and bacteria. Moreover, it was pointed out that examination of unique polymorphic markers would be required to validate a single source of origin. In a responsive commentary, Serafini has argued that because serological AB techniques have proven useful for certain (unrelated) studies in the past, the validity of such findings with relics is therefore convincing, even though environmental conditions are markedly different. In addition, he makes several assertions regarding the extensive use of control groups that confuse results obtained with relics with those of Eucharistic miracles, which should be considered separately. Serafini’s main concern is that excessive scientific prudence will put people off a topic such as the scientific study of Eucharistic miracles. Unfortunately, this viewpoint fails to realize that incautious scientific investigation of such subjects may, in fact, be of much greater harm in the long run. Specific responses to the key points raised in Serafini’s commentary are discussed below.</p>