Elijah asked him: “what I shall do for thee?” And he replied, “a double portion of thy spirit.” And he replied, “Thou hast asked a hard thing.”
The thing is that there is the scrutiny of the 248, and there is the stony heart, which cannot be scrutinized. However, when scrutinizing the 248, the stony heart, too, is thus scrutinized, though it is forbidden to touch in itself. And one who scrutinizes these 248, in doing so he scrutinizes the stony heart, as well.