In Matthew 15:13, it is written ( please read this entire chapter to get the immediate context ), " 13 He answered, t ' Every plant that my heavenly Father has not planted u will be rooted up. '" Jesus ( see Matthew 15:1 ) said this, in response to the disciples telling Him that the Pharisees were offended at His statement that what comes out of the mouth defiles a person. Since Jesus' word is God's word ( see John, chapter 8 ( especially verses 26 and 29, for example ), for example ), this means that the Pharisees were offended at God's word.
Jesus then said to let the Pharisees alone ( see Matthew 15:14 ). Thus, Jesus teaches, here, that we, as Christians, are to leave those people, who are offended at God's word, alone. Jesus did not tell the disciples to prevent the Pharisees from assembling.
Nearly two thousand years later, we are to respond the same way to those who practice false religion, for in Hebrews 13:8, it is written, " 8 Jesus Christ is h the same yesterday and today and forever. " In Jude, verses twelve and thirteen, it is written, " 12 These are hidden reefs5 c at your love feasts, as they feast with you without fear, d shepherds feeding themselves; e waterless clouds, f swept along by winds; fruitless trees in late autumn, twice dead, g uprooted; 13 h wild waves of the sea, casting up the foam of itheir own shame; j wandering stars, k for whom the gloom of utter darkness has been reserved forever. " Jesus said that those who practice false religion, whether they be Baptist, Catholic, Methodist, Mormon, etc., will be uprooted — the gloom of utter darkness has been reserved for them forever.
The lawyers and the politicians have been trying to prevent people from assembling here in America, lately. Those who stubbornly practice false religion and refuse to obey the gospel message have an eternal reservation in hell ( see also 2 Thessalonians, chapter 1 ( especially verses 7-10, for example ), for example ). Since Jesus is the only Way to heaven, and the church of Christ is His body ( see Ephesians 1:15-23 ( especially verses 22 and 23, for example ), for example ), the Bible clearly teaches that it is not possible to be saved outside of the church of Christ. Jesus said, " I am l the way, " for example.