BṚHADĀRAṆYAKA UPANISHAD · 4.2.2

इन्धो ह वै नामैष यो ऽयं दक्षिणे ऽक्षन् पुरुषः ।
तं वा एतम् इन्धं सन्तम् इन्द्र इत्य् आचक्षते परोक्षेणैव ।
परोक्षप्रिया इव हि देवाः प्रत्यक्षद्विषः ॥

indho ha vai nāmaiṣa yo ’yaṃ dakṣiṇe ’kṣan puruṣaḥ ।
taṃ vā etam indhaṃ santam indra ity ācakṣate parokṣeṇaiva ।
parokṣapriyā iva hi devāḥ pratyakṣadviṣaḥ ॥

Yâgñavalkya said: 'That person who is in the right eye, he is called Indha, and him who is Indha they call indeed Indra mysteriously, for the gods love what is mysterious, and dislike what is evident.

F. Max Müller · The Upanishads, Sacred Books of the East 15 (1884)