"Remember that there will be difficult times in the last days. People will be selfish, greedy, boastful, and conceited; they will be insulting, disobedient to their parents, ungrateful, and irreligious; they will be unkind, merciless, slanderers, violent, and fierce; they will hate the good; they will be treacherous, reckless, and swollen with pride; they will love pleasure rather than God; they will hold to the outward form of our religion, but reject its real power. Keep away from such people. Some of them go into people's houses and gain control over weak women who are burdened by the guilt of their sins and driven by all kinds of desires, women who are always trying to learn but who can never come to know the truth. As Jannes and Jambres were opposed to Moses, so also these people are opposed to the truth -- people whose minds do not function and who are failures in the faith. But they will not get very far, because everyone will see how stupid they are. That is just what happened to Jannes and Jambres.
But you have followed my teaching, my conduct, and my purpose in life; you have observed my faith, my patience, my love, my endurance, my persecutions, and my sufferings. You know all that happened to me in Antioch, Iconium, and Lystra, the terrible persecutions I endured! But the Lord rescued me from them all. Everyone who wants to live a godly life in union with Christ Jesus will be persecuted; and evil persons and impostors will keep on going from bad to worse, deceiving others and being deceived themselves. But as for you, continue in the truths that you were taught and firmly believe. You know who your teachers were, and you rememer that ever since you were a child, you have known the Holy Scriptures, which are able to give you the wisdom that leads to salvation through faith in Christ Jesus. All scripture is inspired by God and is useful for teaching the truth, rebuking error, correcting faults, and giving instruction for right living, so that the person who serves God may be fully qualified and equipped to do every kind of good deed."
-2nd Timothy chapter 3
These portions of scripture remind us that there are a lot of people out there who claim to know what they're talking about, but really don't. They deceive people by misrepresenting God. As a result, some people, who don't believe, are quickly turned away from the truth because of some lie they have been told. Even if a person, who speaks about God, means well, no one is perfect.
In one of my college classes, the instructor told the class how she had learned that the virgin Mary had become pregnant by sperm being poured in her ear. I don't know who told her this, but I know it is wrong. The Bible never says anything like that.
Because she used the term "virgin Mary", it may have been a priest who told her. According to the book of Hebrews, we shouldn't even have priests today, and Matthew 23:9 says that we shouldn't call people "father".
I go to church and I listen to my pastor's sermons. Most of what he says is right and can be trusted. However, even he makes mistakes from time to time. The only way that we are able to know when someone is preaching sound doctrine, or not, is to know what the Bible says for ourselves. It's just like what the last quote, from above, says. It's important to turn to scripture for truth. That way, we can know if someone is accurate in what they say.
I'm not naive. If you chose not to believe the Bible before reading this, you'll probably continue to make the same choice after reading it. It's like Jesus said with the parable of seeds scattered on different ground. There are four scenarios that take place when people hear the gospel. In only one of the scenarios does the person bear fruit.
But should you be one of the few who chooses to believe and seek God, the only source that can always be trusted is the Bible. I'm not recommending that anyone not go to church. Just make sure that it's a church that teaches what is true. After all, the Bible encourages fellowship with other believers and says that we should continue to meet together. On this, it says the following:
"Let us not give up the habit of meeting together, as some are doing. Instead, let us encourage one another all the more, since you see that the Day of the Lord is coming nearer."
-Hebrews 10:25