The point here is that salvation is binary. That means that you either know Christ or you are lost. The point the pastor made was that Christ does not allow theological tolerance. It is His way only.
The world is full of false teaching. Christ here tells you that you can tell the quality of the teaching by the fruit it produces. This is echoed in Colossians 2 and 2 Peter 2.
This one is central. Here people were theologically correct, engaged in prophecy, and working miracles. Yet Christ says they were workers of wickedness and never knew them. One can know the right doctrine, be engaged in spiritual and Christian service and not be known by Christ.
That brings us to the last section. The foundation has to be right. That is a personal relationship with Christ. Nothing else matters. That is the 1 of the binary. Knowing Christ is all that matters.