When a house sits on a foundation that has not been properly prepared, over time the storms and elements will slowly undermine the foundation—until suddenly the house collapses. Jesus gave us a picture of this in the Sermon on the Mount. Jesus depicted two houses: one built on sand, and the other built on the foundation of a rock. When the floods came, the house built on the foundation of sand fell, but the house built on the foundation of rock stood the test and survived the storm. This book will reveal to us the telltale signs of the erosion of our spiritual foundations.