Many will say to me on that day, 'Lord, Lord, did we not prophesy in your name, and in your name drive out demons and perform many miracles?' Then I will tell them plainly, 'I never knew you. Away from me, you evildoers!'
There are many interesting things about this passage, but there are two things that I don't think should be passed by.
One is the surprise of these people. You can almost sense it in their response. They are crying out, "...didn't we do enough? Didn't we do what we were supposed to be doing? How is this possible?!?" They were going through life thinking, and believing that they were OK. But they were self-deceived.
The other thing that I would like to point out is the very first word, "Many..." That word is frightening. There are going to be many people who fall into this category. Jesus tells us in another place that the road is wide that leads to destruction, and many will find it.