Limits
Walls keep everybody out. Boundaries teach people where the door is (Mark Conner, motivational speaker)
Walls are important defenses that prevent unwanted invasions of your property. Boundaries are important, too, because they help people recognize their limits. Both keep us from being hurt. Walls may have a locked gate, but boundaries willmost likely have a door where friends can come and go freely.
Guard your heart above all else, for it determines the course of your life (Proverbs 4:23).