A boundary has two purposes; keep something out and to keep something in.
You need to have boundaries in your life starting with your mind and spirit to keep some things out.
Start will keeping yourself from being influenced by false religion.
There are plenty of so-called churches, ministers, and cults looking to separate you from Christ.
Jesus said, “Beware of false prophets who come disguised as harmless sheep but are really vicious wolves.” Matt 7:15
Likewise, don’t be influenced by fake teaching.
Those that are head of false religions are very good at presenting a teaching that leads to nothing but death and destruction. They do not have the words of life.
For such are false apostles, deceitful workers, transforming themselves into apostles of Christ. And no wonder! For Satan himself transforms himself into an angel of light. Therefore it is no great thing if his ministers also transform themselves into ministers of righteousness, whose end will be according to their works. 2 Cor 11:13-15
For the immature Christian, even a small amount of deception can lead to problems. This false teaching is like a little yeast that spreads through the whole batch of dough! Gal 5:9
Finally, there needs to be a boundary around your mind and spirit so that you will not be influenced by flattering words.
For a time is coming when people will no longer listen to sound and wholesome teaching. They will follow their own desires and will look for teachers who will tell them whatever their itching ears want to hear. They will reject the truth and chase after myths. 2 Tim 4:3-4
You need to be in a church that challenges you; a church that has a message that convicts you and gives you a desire to improve your life and relationship with Jesus.
If you are in a church and feel nothing but comfort then you may be falling prey to flattering words.
Set a boundary around your mind and spirit to keep these things out and to keep Christ in!