Pañcadaśī 4-27

Ātma-vichāra or the contemplation upon the nature of the self as Brahman, conforms with the scriptures, but even this duality is to be renounced after Brahman is understood fully. The śrutis advises to not engage with too many words. Two verses are given to elucidate this “Know only that one and give up all other talk” (Muṇḍaka, 2.5) and “A wise person should resolve oneʼs speech in the mind” (Kaṭha, 3.13)