Commentaries:
Robertson's Word Pictures (NT)
He that is not against us is with us (ov ouk estin kaq hmwn uper hmwn estin). This profound saying throws a flood of light in every direction. The complement of this logion is that in Matthew 12:30: "He that is not with me is against me." Both are needed. Some people imagine that they are really for Christ who refuse to take a stand in the open with him and for him.
Other Robertson's Word Pictures (NT) entries containing Mark 9:40:
Luke 9:50
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