Shiva Purana
स्वदेहेगलिते पूर्णं शिवं प्राप्नोति निश्चयः । केवलं मंत्रजापी तु योगं प्राप्नोति निश्चयः ११ ।
When the body is destroyed he completely merges in Śiva undoubtedly. The mere repeater of the mantra attains the yogic communion with Śiva certainly.
english translation
svadehegalite pUrNaM zivaM prApnoti nizcayaH । kevalaM maMtrajApI tu yogaM prApnoti nizcayaH 11 ।
hk transliteration by Sanscript