There was a charge to get into this concert, but it was free to me because my date (Ken) paid for it.
Salvation is free to us. But Salvation has a price, too....Jesus paid for it with his life. Perhaps that is why we think following Jesus doesn't cost anything--because we didn't pay for it? But it does cost something, and we are told to count those costs so we aren't caught off-guard. We can't be a follower of Jesus without having our lives changed. It will be for the better, but the flesh may beg to disagree! God says we are to be in the world, but not of it. Counting the cost helps us understand the difference.