Why does a person become a liar?
Chapter 3, – Bhagavad Gita, (Spiritual India Podcasts in Hindi | Manoj K Dwivedi)He whose inner and outer organs of senses are not conered because of his sins not being annulled but is none the less struggling for winning knowledge of the self, whose mind is forced to turn away from the self by reason of it being attached to sense objects, and who conseently lets his minds dwell on them - he is called a hypocrite, because his actions are at variance with his professions. The meaning is that by practising the knowledge of the self in this way, he becomes perverted and lost.