Bhagavad Gita 10.38

I am the scepter of rulers, the strategy of conquerors, the silence of mystery, and the wisdom of the wise.

दण्डो दमयतामस्मि नीतिरस्मि जिगीषताम्।
मौनं चैवास्मि गुह्यानां ज्ञानं ज्ञानवतामहम्॥

daṇḍo damayatāmasmi nītirasmi jigīṣatām|
maunaṃ caivāsmi guhyānāṃ jñānaṃ jñānavatāmaham||

English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).