“Those whose intelligence has been stolen by material desires surrender unto demigods and follow the particular rules and regulations of worship according to their own natures.”
[Bhagavad Gita 7:20]

“Ekam evadvitiyam”
“He is One only without a second.”
[Chandogya Upanishad 6:2:1]1

“Na casya kascij janita na cadhipah.”
“Of Him there are neither parents nor lord.”
[Svetasvatara Upanishad 6:9]2

“Na tasya pratima asti”
“There is no likeness of Him.”
[Svetasvatara Upanishad 4:19]3

“Na samdrse tisthati rupam asya, na caksusa pasyati kas canainam.”
“His form is not to be seen; no one sees Him with the eye.”
[Svetasvatara Upanishad 4:20]4