Chandogya Upanishad 2.15.2

2.15.2

sa ya evam etad vairūpaṃ parjanye protaṃ veda \
virūpāṃś ca surūpaṃś ca paśūn (S ) \
sarvam āyur eti \
jyog jīvati \
mahān prajayā paśubhir bhavati \
mahān kīrtyā \
varṣantaṃ na nindet \
tad vratam \\215.2\

He who thus knows this Vairūpa Sāman as woven in the rain-cloud acquires cattle of handsome and manifold forms, reaches the full length of life, lives gloriously, becomes great with offspring and cattle and great also with fame. His holy vow is that he should not find fault with the rain-cloud when it rains.