"I Never Knew You"

As a young Christian, of which I still am, though further along than I was before, many things in the Word confused and puzzled me. Today I read one of the passages that always worried me as a very young Christian, and yet today, as I passed it over, it no longer concerns me---at least not in the same way. 
Having heard other people find the passage "frightening", I will do a quick discourse on the passage. 

21“Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but only the one who does the will of my Father who is in heaven. 22Many will say to me on that day, ‘Lord, Lord, did we not prophesy in your name and in your name drive out demons and in your name perform many miracles?’ 23Then I will tell them plainly, ‘I never knew you. Away from me, you evildoers!’Matt 7 NIV

Now, for me, as silly as it may be for some readers, and a reality for others, used to frighten me. Mainly, I figured out, because there is a "title" break in most Bibles between this passage and the previous section. The more I study, the more I find those title breaks, even if I do not read them, damaging to the flow of my reading. A new chapter started, the previous section is not immediately connected or some such thing. 

This passage is speaking about false prophets---false teachers. 

The topic at my women's Bible study this quarter is Discernment. Knowing how to see when books, people, teachers, pastors are misled, whether on purpose or by accident. 

We all will make mistakes with the Word, but should, of course, try to limit those. Speaking to other believers, especially those who have studied greatly, listening to sound teaching, checking the Word for what He says assists us in these matters. 

There are many people in the world, though, that search the world for "easy marks" to get money from, fame from, whatever they might want. These people learn how to walk the walk, talk the talk, and then, with their "heart" in their eyes, walk off with their god, money, fame, whatever. 

But they never really did have faith in God. 

It is not, I don't think, this passage's intent to tell us that we who believe are in great danger of being told "I never knew you", no. It is the intent to warn us that not all who teach are honestly teachers. 

The best tool we have to measure teaching by is God's Word. Therefore, we have to know it. We cannot rely too much on other books---and the books we love to read for devotionals etc., must line up with the Word. 

The Bereans listened to Paul as He spoke, but they checked everything He said with scripture first before agreeing with him. It behooves us to do the same. It is too easy for heresy to enter into us from a seemingly "solid" teacher, book, song or what have you. 

How easy was it for Satan to trick Eve into saying things God did not say? (Read Genesis, and note the differences she added to what God said in His actual commands). It is terribly easy for errors, mistakes, misreads, misquotations, out of context verses/passages can be impossible to spot without due diligence.