Overview

One thing to consider when looking for information is that there is a lot of misinformation (accidentally incorrect) and disinformation (intentionally incorrect) – both directed by the Enemy. So, how do you know what’s right and true? Here’s my opinion:

1. Bible Translation – a big part of this starts from the Bible translation. Again, from everything I can tell, KJV and NKJV is the most authoritative source that exists. The other more-readable versions (e.g. NIV, NASB, etc.) all start getting a bit “loose”. Then, you have churches that have written their own Bible – which we know those to be false. See: What about Bible versions?
2. Discernment – when the Holy Spirit dwells within us, we get insight and nudges. You can think of it like our conscience and our gut feeling, plus much more. We can know a Godly source “by their fruit” – which means you can tell if something is coming from a good place or bad place. This gets more difficult with charismatic pastors who are excellent at appearing proper and good. Nonetheless, our instincts via the Holy Spirit can give us a sense of when something is good or bad. See: Discernment – How to know truth?

If you are new to this Christianity topic, you might have guessed that the Enemy spends a lot of time trying to mess it up. So, there becomes a lot of “noise” to distract the believer. We need to wade through the nonsense to get to the truth. Luckily the truth is always available to us, directly – that is the Bible.

Pastor [X] is a false teacher!

For every pastor you might find, especially nationally known ones, you will find blogs and websites claiming that some certain pastor is a false teacher. Sometimes, those accusers are right. Sometimes, those accusers are instruments of the enemy. In my opinion, it’s probably something more like this:

Every Christian pastor you run across is going to fall somewhere on this scale. Let me explain these in a bit more detail for context.

False Teachings (in either extreme)

Regular False teachings are pretty easy to identify because there is a single source of truth, the Bible. So, you can go look things up for yourself. You might find at that point, that the pastor is using some questionable translation. For more on the significance of Bible translations, see: What about Bible versions?
False Teachings on the left tend to get looser and looser with the Bible to the point where they’ve made up a new religion. False Teachings on the right tend to get so uptight, angry, and militant, that they too – totally lose the message and create a new religion.

Progressive / Prosperity Gospel

In the past several years there has been a dramatic rise in these categories (which I’m putting into one category). Progressive Christianity is the concept of Christianity, but basically take away any of the rules or rigid requirements. It’s this notion that all God wants is for everyone to get along – which is not the message of the Bible. Like, at all. The intent seems to be to allow and embrace sinning, so that more people come to Christ (albeit under false pretenses).
This denomination of “Christianity” welcomes Muslims, Jews, practicing homosexuals, all under one umbrella where everything is great. It’s a nice gesture, but it’s not Biblical.
Prosperity Gospel is the concept of: God primarily wants you to have an awesome life here on Earth. The intent seems to be to just tell people what they want to hear, instead of the Truth about what this relationship is about. Leaders in this category tend to be charismatic, and tend to center things on themselves – and teach listeners to build up their lives, as opposed to trusting in, and building up a relationship with the Lord.
Some examples of Progressive and/or Prosperity Gospel teachers are: Joel Osteen, Hillsong, Bethel, Lakewood, Elevation Church, etc. I’ve also come to realize that although not as egregious, Joyce Meyer and Andy Stanley are over the line on a few topics.

Legalism

On the other end of the spectrum is legalism. That is the concept of getting so caught up in the rules and regulations, that it gets in the way of the message. It also becomes a source of ego and pride too. This is your “holier than thou” type that pridefully tells you all of the ways that you are not measuring up. Legalism tends to lead believers down a path where they feel “works” (things they do) become important for salvation. Like, you really need to try hard and prove your worth, to be saved – which is not Biblical. So, it too, is not ideal. For more on “being saved”, see: Sin and Getting Saved.

The Truth

Amongst all of these fallible, imperfect humans trying to get the message out – there is the actual, one truth. The good part is that we have this available to us – so we can use it to discern who is speaking the truth and who is missing the mark.
In my opinion: I think so long as a pastor is teaching the core tenets correctly, then that is a good place to start. Just be diligent. I watched a lot of Joyce Meyer and a lot of Andy Stanley which helped me get into the Word. I later learned that some of their teachings were not correct and not Biblical. So for me, these teachers still served a purpose and can help people find their way to the Lord – but you must also do your own, independent study. You cannot fully trust any pastor, preacher, or priest. They are all, after all, human. Your life, your soul, and your salvation is in your own hands – be diligent.