Bhagavad Gītā Chapter Four verse 10

vītarāgabhayakrodhā manmayā mām upāśritāḥ |
bahavo jñānatapasā pūtā madbhāvam āgatāḥ ||

jñāna - knowing; knowledge; higher knowledgetapas - to heat; religious austerity; self-disciplinevīta - free from; smoothrāga - colour; attraction; delight in; vehement desire of; a musical note, harmony, melody