“But whoever causes one of these little ones to stumble, it would be better for him to have a heavy millstone hung around his neck, and to be drowned in the depth of the sea” (Matthew 18:6).
Jesus set a child before those disciples concerned with greatness (v.1). It was intended as a lesson not about innocence (such sentiment betrays the rigors of carrying the cross and the hardness of the world in which faith must be lived out) but, rather, having an eye for ministry that focuses on the littlest (mikron) of people and our responsibility before them. This isn’t so much a biological (age) issue as it is sociological (position). Ego wants to do big things for big people; that one’s status might be elevated. Little things for little people, however, who can offer nothing in return, is the only true Kingdom work. The question of greatness is itself a stumbling block because it introduces a concern for status that God’s kingdom does not even invite.