Jamieson, Fausset and Brown on Luke 18:15

Lu 18:15-17. Little Children Brought to Christ.

15. infants--showing that some, at least, of those called in Matthew (Mt 19:13) and Mark (Mr 10:13) simply "little" or "young children," were literally "babes."

touch them--or, as more fully in Matthew (Mt 19:13), "put His hands on them and pray," or invoke a "blessing" on them (Mr 10:16), according to venerable custom (Ge 48:14, 15).

rebuked them--Repeatedly the disciples thus interposed to save annoyance and interruption to their Master; but, as the result showed, always against the mind of Christ (Mt 15:23; Lu 18:39, 40). Here, it is plain from our Lord's reply, that they thought the intrusion a useless one, as infants were not capable of receiving anything from Him. His ministrations were for grown people.