Four things calculated to remove fear, cause fear when improperly done-Agnihotra, the vow of silence, the vow of study and that of sacrificial ceremonies.
चत्वारि कर्माण्यभयंकराणि भयं प्रयच्छन्त्ययथाकृतानि। मानाग्निहोत्रमुत मानमौनं मानेनाधीतमुत मानयज्ञः॥