Every one who hears these words of mine and does them will be like a man wise enough to build his house on rock. When the rain falls and the floods come, when the winds blow and beat upon that house, it will not fall; because it's been built on solid rock.
Every one who hears these words of mine and does not do them will be like a man so foolish he builds his house upon sand; and when the rain falls, and the floods come, when the winds blow and beat against such a house, it will fall; and great will be that fall.
Yes, I've taken liberties with the tenses, and lost whatever topical reference this might have had to Jesus' time (perhaps to people who depended on Roman power to keep them safe -- or alternatively, people who'd taken God's help for granted in pointless insurrections against Rome and the powers that be...) but then this always did imply that future application. To understand Jesus' words and live by them will turn out to be the true practicality; to trust in worldly 'practicality' instead will leave anything you accomplish subject to collapse in this turbulent world.
This applies, of course, to his whole preceding discourse. Is it really so 'impossible' as people have said -- or haven't we understood?