Simplify the following text for a Grade 9 native English-speaking person.
Original: Someone practicing deep meditation ( such as in raja yoga ) must embody the core principles of karma yoga , jnana yoga and bhakti yoga , whether directly or indirectly .
Simplified: The yoga referred to here , however , is specifically Raja Yoga ( or meditational union ) . It is based on the sage Patanjali 's text called the Yoga Sutra , which is about the Yoga philosophy that came before .