Recently, it was said that a percentage of Americans are changing from the religion of their childhood. Well, that can be a good thing or it can be a bad thing.
For example, the Bible teaches that Jesus built one church (Matthew 16:18). Also the Bible warns of the existence of false doctrine (2 Peter 2:1-2; Colossians 2:8:18). Now consider this, if one is a member of a church that the Lord didn’t establish, that person is in false teaching (Mark 7:7; Matt. 15:13-14; 2 John 7-11).
In order to be saved, one must leave error behind and that is a good thing. But on the other hand, if one is in a church where the truth is taught, and he leaves that church after falling victim to false teaching; that is bad (2 Peter 3:14-18).
Since it is possible to be wrong, one shouldn’t leave a church unless that church is proven by the word of God to be in error (Acts 18:24-28, 19:1-5).