“Anyone who goes too far and does not abide in the teaching of Christ, does not have God; the one who abides in the teaching, he has both the Father and the Son. If anyone comes to you and does not bring this teaching, do not receive him into your house, and do not give him a greeting; for the one who gives him a greeting participates in his evil deeds.” (2 John 9-11)
False teachers must be rejected from our homes when they come specifically to promote falsehood.
Your door knocks, and it’s a false teacher. As often happens, he wants to give you literature. How are you to respond? The book of 2 John helps give an answer.
This little book tells us exactly how to deal with false teachers that try to bring their heretical teaching to your home. His clear command is that we are to not allow such a one to enter your home if his purpose of coming to you is to teach his false teaching (v10a). One is not even to give a blessing to such a person (v10b). The heretic who actively promotes their doctrine should be soundly rejected.
Now, the heretic still needs to be saved, so how can we reach them? Having an unbeliever who believes falsehood in your home is different than having a person who promotes it (see v8a, “If anyone comes to you” emphasis mine). We should see to win such a person to the truth (see 2 Tim. 2:24-26), but not on their terms of evangelizing us. Additionally, we can and should have unbelievers who are in need in our home as well (see Heb. 13:2a), but only if they are not coming for the express reason to promote their falsehood.
We live in a dangerous world with many false beliefs (c.f. 1 Tim. 4:1-4). We must be on guard, and reject anyone who tries to promote their falsehood to us. But, lets have conversations on our terms with those trapped by false teachings so we can save them.