Bhagwad Gita
Chapter 4, Verse 39
श्रद्धावाँल्लभते ज्ञानं तत्परः संयतेन्द्रियः।
ज्ञानं लब्ध्वा परां शान्तिमचिरेणाधिगच्छति।।4.39।।
A faithful man who is absorbed in transcendental knowledge and who subdues his senses quickly attains the supreme spiritual peace.