Now John answered Him, saying, "Teacher, we saw someone who does not follow us casting out demons in Your name, and we forbade him because he does not follow us." But Jesus said, "Do not forbid him, for no one who works a miracle in My name can soon afterward speak evil of Me.
Mark 9:38-39

Here Jesus says that just because someone is not “with us,” that does not mean the person is “against us.” Yet in another place (Matthew 12:30), Jesus said that if a person is not “for us,” the person is against us.” Which is it?

Though it may seem like it, this is not a contradiction—if we understand both the two contexts and the heart of the Lord Jesus.

In the first instance, the meaning is that just because a person is not apart of our group, that doesn’t necessarily mean he is against us. Such is the case with Christians who are not all members of the same church or group of churches. We do not all have to agree on every detail.

However, when a person does not adhere to the essentials of the faith, that person is not with Christ, even though that one identifies him/herself as a Christian.

The challenge is to discern which matters are weighty enough to say we must be in agreement, and which matters leave room for differences. The bottom line is not whether people are one with our group, but are they one with Christ and the gospel? And when in doubt, let us seek to be more gracious than rigid.