Jesus compares the person who hears but does not obey his teaching to a man who builds a house that has no foundation and so will collapse when the flood comes. (See: [[rc://en/ta/man/translate/figs-simile]])
Some cultures may not know that a house with a foundation is stronger. Additional information may be helpful. Alternate translation: "but he did not dig down and build first a foundation" (See: [[rc://en/ta/man/translate/figs-explicit]])
the part of a house that connects it to the ground. People in Jesus' time dug down into the ground to the solid rock and then began to build on the rock. That solid rock was the foundation.