In plain words
Awareness belongs to the Self as heat belongs to fire. It shines, one and unwavering; through it, mind and senses carry out their functions. I am that Self whose very form is knowing, ever established.
Word for word
As heat belongs to fire, His nature is eternal awareness; He shines as one, without change. Depending on Him alone, the insentient inner instrument, senses and the rest proceed with their functions. I am that Self whose form is knowledge, ever established.