18:19,20
“I will call to account ...” We see more of the importance of Jesus, and of listening to Him. This is then followed by a warning against false prophets. Claiming to speak on God’s behalf, or to speak in the name of other gods was direct disobedience to God, and would potentially lead the people astray. Such a person was to be put to death. False teachers are not to be tolerated.
18:21,22
With all these warnings about false prophets, the natural question is how can we tell if someone is a false prophet, i.e. speaking a message that is not from the Lord. Earlier we had the test that if their teaching enticed people away from God towards idols, then it was not from God. Here we get a very simple test. If what they say does not take place then it is not from the Lord. Such a person can be ignored. Today all prophecy should be tested, just because someone claims to speak the word of the Lord does not mean they are doing so. Note that it does not say that if what they say does come true, then they are speaking in God’s name (Deut 13:1-4).