They lived in the house for one year, watchfully protecting themselves from Purochana. In the meantime they dug a subterranean passage according to the directions of Vidura.
पुरोचनाद्रक्षमाणाः संवत्सरमतन्द्रिताः। सुरुङ्गां कारयित्वा तु विदुरेण प्रचोदिताः॥