Shiva Purana

siva.sh/siva-purana/saturda-samhita/26/24

एतस्मिन्व्यवहारे तु प्रमाणं शशिभास्करौ ।। त्रिवारं सत्यमित्युक्त्वा हृदयं मे स्पृश प्रिये ।। २४ ।।

sanskrit

In this deal the witnesses are the moon and the sun. Repeat three times “True” and touch my heart, O beloved.

english translation

etasminvyavahAre tu pramANaM zazibhAskarau || trivAraM satyamityuktvA hRdayaM me spRza priye || 24 ||

hk transliteration by Sanscript