The goal of this article is to look at the literary-theological function of the Jewish religious leaders hardening in Mark 3:1-6. In this text, the concept of "hardness of heart" is used in order to indicate their continued unbelief and rejection. The hardening may also be signaling their presumed end, namely divine judgment (cf. 12:1-2). Although Jesus proclaims the arrival of the kingdom in his authoritative teaching and miracles, the Jewish religious leaders refuse to Jesus' message, as Pharaoh, whose heart is hardened, refuses to obey God's commend. Just as his hardening and rejection allows the plagues to be multiplied as a great judgment (Ex. 7:3) and the catastrophe at the sea (Ex. 14:4, 8, 14), the Jewish religious leaders' unbelieving rejection by their hardening will allow God's judgment. Thus, with regard to the Jewish religious leaders, the concept of "hardness of heart" identifies their unbelief and hostility. It is not simply innocent incomprehension, but an intended rejection.