Sankaracarya's Vivekachudamani 439

विज्ञात आत्मनो यस्य ब्रह्मभावः श्रुतेर्बलात् ।

भवबन्धविनिर्मुक्तः स जीवन्मुक्तलक्षणः ॥

vijñāta ātmano yasya brahmabhāvaḥ śruterbalāt |

bhavabandhavinirmuktaḥ sa jīvanmuktalakṣaṇaḥ ||

(Sankaracarya's Vivekachudamani 439)

One who has realized that the Self is Brahman, affirmed by the scriptures and free from the bondage of becoming* (transmigration)---this is the indication of a jivan-mukta.