Shiva Purana
सप्तधैवाभिमंत्र्याथ प्रणवेन पुनश्च तम् ॥ यस्त्वन्तरं किंचिदस्ति कुरुते त्यतिभीतिभाक् ॥ ३५ ॥
Then he chanted the sevenfold mantra and again chanted the oṁkāra. He who makes any difference is very afraid.
english translation
saptadhaivAbhimaMtryAtha praNavena punazca tam ॥ yastvantaraM kiMcidasti kurute tyatibhItibhAk ॥ 35 ॥
hk transliteration by Sanscript