Chapter 2 · The Yoga of Knowledge · Krishna said
Bhagavad Gita 2.29 — The wonder of the soul
आश्चर्यवत्पश्यति कश्चिदेन- माश्चर्यवद्वदति तथैव चान्यः। आश्चर्यवच्चैनमन्यः शृणोति श्रुत्वाप्येनं वेद न चैव कश्चित् ॥
āścaryavatpaśyati kaścidenam āścaryavadvadati tathaiva cānyaḥ | āścaryavaccainamanyaḥ śṛṇoti śrutvāpyenaṃ veda na caiva kaścit ||
Meaning
Some see the soul as a wonder, some speak of it as a wonder, some hear of it as a wonder — and even after hearing, no one truly knows it.