46 And a reasoning came in amongst them, who should be [the] greatest of them. 47 And Jesus, seeing the reasoning of their heart, having taken a little child set it by him, 48 and said to them, Whosoever shall receive this little child in my name receives me, and whosoever shall receive me receives him that sent me. For he who is the least among you all, he is great.
49 And John answering said, Master, we saw some one casting out demons in thy name, and we forbad him, because he follows not with us. 50 And Jesus said to him, Forbid [him] not, for he that is not against you is for you.
Matthew Henry's Commentary on Luke 9:46-50
Commentary on Luke 9:43-50
(Read Luke 9:43-50)
This prediction of Christ's sufferings was plain enough, but the disciples would not understand it, because it agreed not with their notions. A little child is the emblem by which Christ teaches us simplicity and humility. What greater honour can any man attain to in this world, than to be received by men as a messenger of God and Christ; and to have God and Christ own themselves received and welcomed in him! If ever any society of Christians in this world, had reason to silence those not of their own communion, the twelve disciples at this time had; yet Christ warned them not to do the like again. Those may be found faithful followers of Christ, and may be accepted of him, who do not follow with us.