Context: Jesus, in the Sermon on the Mount, teaches first in the Beatitudes that the Kingdom of God is attained by those who yield themselves to the Almighty, and then declares that He has come not to destroy the old law, but to fulfill it. Praising those who follow His teaching and promising them their reward in Heaven, He enlarges the old old law against murder to include a new law against anger. Further, He extends the old law against adultery to prohibit lust. If the right eye, He says, causes one to lust, then it should be plucked out. Expanding the example, He cites another part of the body:
And if thy right hand offend thee, cut it off, and cast it from thee: for it is profitable for thee that one of thy members should perish, and not that thy whole body should be cast into hell.