How do I get past that sentry

Hint 1 of 4:

You realize that he's the guard for the guru who wrote that book.

Hint 2 of 4:

The one about lowering golf scores.

Hint 3 of 4:

The one you bought from the devotee in the airport.

Hint 4 of 4:

Maybe if you gave him the book, so he would know that you belong inside.