Mark 9:40

For he that is not against us is on our part] Much to be preferred is the more pointed version of Lk, which is also strongly attested here: 'For he that is not against you is for you' (Lk RV). The meaning is, The man, though without your apostolic commission, was doing, and doing successfully, the very same benevolent work that you were doing. You ought, therefore, to have esteemed him a friend and a helper, not an enemy. A jealous and exclusive spirit is unworthy of the ministers of Christ.