Satchitananda (existence-consciousness-bliss) is what we contact in deep meditation. It is what rises in us as silence, also called the "witness state". Stabilization of this transcendent reality as our sense of self 24/7 is the first stage of enlightenment. The phrase "pure bliss consciousness", used often in the lessons, is synonymous with satchitananda, inner silence and witness. Bliss is a key word in this. The immutable inner witness is a blissful one and so are we when we become it. And there is much more to come after that.
Click on "Main Lessons" above to begin the path to the witness state or read more here: Lesson 122 - Witnessing