The very heart and root of sin is an independent spirit. We erect the idol self, and not only wish others to worship, but worship it ourselves.
“And when you pray, you shall not be like the hypocrites. For they love to pray standing in the synagogues and on the corners of the streets, that they may be seen by men. Assuredly, I say to you, they have their reward. But you, when you pray, go into your room, and when you have shut your door, pray to your Father who is in the secret place; and your Father who sees in secret will reward you openly.”
The New King James Version