My boss is very religious and a disciple of one path in India. He is drawing a handsome salary and uses his professional position to serve his religion's saint, giving donations and spending for other religious functions. But in the process he doesn’t give priority to his work and nor he is regular in attendance, and also arrogant in behavior. As a result the owners of the organization are displeased with him. Is he doing the right thing in the name of religion & God?
Although some aspects of what your boss is doing might seem unethical, the fact is that neither you nor I know the full picture. If we did know it, things might look quite different; it is hard to say.
In any case, you are not responsible for his behavior, nor are you responsible changing him. Given that, you can let God and the owners sort out this situation, while you focus on doing your best by your own ethical standards, and not being judgmental. It would also be good to pray for his highest welfare, and not criticize him when speaking with others.