6.21 Yatra, when, at the time when; vetti, one experiences; tat, that; atyantikam, absolute-which is verily limitless, i.e. infinite; sukham, Bliss; yat, which; buddhi-grahyam, can be intuited by the intellect, intuited by the intellect alone, without the help of the senses; and which is atindriyam, beyond the senses, i.e. not objective; (-when one experieneces this kind of Bliss) and sthitah, being established in the nature of the Self; ayam, this person, the illumined one; eva, surely; na calati, does not swerve; tattvatah, from that Reality-i.e. does not deviate from the nature of Reality-.
Further,