Shankara speaks about the True Self

“प्रातः स्मरामि हृदि संस्फुरदात्मतत्त्वंसच्चित्सुखं परमहंसगतिं तुरीयम् ।यत्स्वप्नजागरसुषुप्तिमवैति नित्यंतद्ब्रह्म निष्कलमहं न च भूतसङ्घः ॥१॥ prātaḥ smarāmi hṛdi saṃsphuradātmatattvaṃsaccitsukhaṃ paramahaṃsagatiṃ turīyam |yatsvapnajāgarasuṣuptimavaiti nityaṃtadbrahma niṣkalamahaṃ na ca bhūtasaṅghaḥ ||1|| At dawn, I meditate in my heart on the truth of the radiant inner Self.This true Self is Pure Being, Awareness, and Joy, the transcendent goal of the great sages.The eternal witness of the waking, dream and deep sleep states.I am more than my body, mind and emotions, I am that undivided Spirit.