He that is not with me is against me; and he that gathereth not with me scattereth abroad.

People's New Testament

12:30 He that is not for me, etc. The two kingdoms of Satan and of Christ are opposed. No neutrality is possible. He that is not for me is against me.

Wesley's Notes

12:30 He that is not with me is against me - For there are no neuters in this war. Every one must be either with Christ or against him; either a loyal subject or a rebel. And there are none upon earth, who neither promote nor obstruct his kingdom. For he that does not gather souls to God, scatters them from him.

Jamieson-Fausset-Brown Bible Commentary

30. He that is not with me is against me; and he that gathereth not with me scattereth abroad-On this important parable, in connection with the corresponding one (Mt 12:43-45), see on [1278]Lu 11:21-26.

Matthew Henry's Concise Commentary

12:22-30 A soul under Satan's power, and led captive by him, is blind in the things of God, and dumb at the throne of grace; sees nothing, and says nothing to the purpose. Satan blinds the eyes by unbelief, and seals up the lips from prayer. The more people magnified Christ, the more desirous the Pharisees were to vilify him. It was evident that if Satan aided Jesus in casting out devils, the kingdom of hell was divided against itself; how then could it stand! And if they said that Jesus cast out devils by the prince of the devils, they could not prove that their children cast them out by any other power. There are two great interests in the world; and when unclean spirits are cast out by the Holy Spirit, in the conversion of sinners to a life of faith and obedience, the kingdom of God is come unto us. All who do not aid or rejoice in such a change are against Christ.