In two places, penalties mentioned in the Sermon on the Mount are conspicuously absent in the Sermon at the Temple. First, the Sermon on the Mount teaches that anyone who "shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven" (Matthew 5:19), but the Sermon at the Temple mentions no such punishment or criticism. Second, where the Sermon on the Mount says, "If thy right eye offend thee, pluck it out, . . . and if the right hand offend thee, cut it off" (Matthew 5:29-30), the Sermon at the Temple simply gives the commandment "that ye suffer none of these things to enter into your heart" (3 Nephi 12:29).
Interestingly, the Sermon on the Mount has been subjected to considerable criticism by commentators on account of these two passages. On the one hand, some have argued that the drastic punishment of one who breaks even the least commandment seems grossly disproportionate to the crime and, uncharacteristically, too legalistic for Jesus to have said. On the other hand, the suggestion of bodily mutilation seems wholly inconsistent with the extraordinary Jewish respect for the human body, and seems at odds with the other statement in the Sermon on the Mount that one should cast the beam from one's eye (but not cast away the eye). None of these problems arises, however, in the Sermon at the Temple. Indeed, the absence of these problematic passages here can even be used to support the idea that these two passages were not originally parts of the Sermon on the Mount, as some commentators have suspected. [John W. Welch, The Sermon at the Temple and the Sermon on the Mount, F.A.R.M.S., p 103]