In plain words
'Who am I? How is there liberation? By what is one caught in this cycle of worldly existence? This very reflection, the wise who know its meaning declare to be tapas.'
Who am I? What is this doership of mine? Why this enjoyership of mine? For what reason do birth, death, and all the rest occur? How has this worldly existence come upon me? Is there liberation from it? Inquiry into such matters is itself the great tapas, so the ṛṣis used to say. The effort behind such inquiry is itself tapas — the fruit of the soul's own discrimination. This is the very first step. As soon as this step is climbed, taking the scriptural teaching as one's guide — 'The Ātma is to be heard, to be reflected upon, to be meditated upon' — and crossing, in due order, stages such as these, one can attain liberation, the final destination. That is, the Śruti shows the path of release from this world, which is itself a construction of the seen. Such a guide, such an instructor in this path, is God alone; no other guru can do this. 'Let him approach a guru who is learned in the Vedas and firmly grounded in Brahman' — that is, one must approach only a guru who possesses both learning in the Vedas and grounding in Brahman — so the Śruti declares. Here, being 'learned in the Vedas' means being rich in good conduct — that is, one who conducts himself in accordance with the Śrutis and with tradition. Being 'grounded in Brahman' means: one free of doubt and misapprehension, endowed with unshaken Ātma-jñāna, who, having no worldly attachments of any kind, thinks of, lives, and demonstrates everything as the very form of Brahman — knower of the three times, beyond the three guṇas, and of one non-dual disposition,