Luke 9:48

and said unto them, Whosoever shall receive this child in My name receiveth Me; and whosoever shall receive Me receiveth Him that sent Me; for he that is least among you, the same shall be great.

Just how great the spiritual denseness of the disciples was even at that time, appears from this incident. For while Jesus was concerned about the work of salvation, about the woe and weal of the whole world, the apostles were bickering, in petty jealousy, about rank in their own midst. There was a regular altercation about the question in their circle on this trifling matter. Luke does not relate that Jesus asked them about their dispute, being content to point out the lesson which Jesus taught. The Master took a little child and placed it beside Him as He was standing in their midst, telling them that by receiving this little child they would receive Him, and therefore also Him that sent Him. The little and insignificant in the eyes of the world is great in the eyes of Jesus, if there is faith to be found. And then He states the great paradox, the apparent contradiction which holds true in the kingdom of God: He that is smaller than all, he is great in the kingdom of God. He that is satisfied with the humblest, lowest position, if he can but serve the Master, he has the true qualities that make for greatness, and will be acknowledged in that way by Christ Himself.