These two things : World is an Illusion and World is Brahman.
We have to sort it out.
And for that this text called "Tripura Rahasya" is studied.
The entire text has been delivered in the form of Spiritual Discourses by Swami Anubhavananda Saraswati (the Smiling Swami).
These talks are provided here as podcasts for the desiring seeker of Truth.