Matthew 7:24-27 compares and contrasts 2 builders. One builds on the rock, that is he puts Jesus' words into practice. He obeys. The other builder builds on sand. That is, he doesn't obey. When the storm struck his house fell. Here is the interesting thing. It didn't fall before the storm. It looked fine. His house stood during good weather. That can be like us. We seem do be doing fine, then a storm hits and our true condition is revealed. 

In reading Matthew 7:21-23, it seems that the person is surprised that they won't be staying in heaven. They list all their great works for God. Jesus tells them, "depart from Me." This passage should cause us to grapple hard with our faith to make sure we are Christians. Do you think there will be surprises in heaven?