Shiva Purana

siva.sh/siva-purana/vishweshwara-samhita/3/18

ब्रह्मोवाच । साध्यं शिवपदप्राप्तिः साधनं तस्य सेवनम् । साधकस्तत्प्रसादाद्योऽनित्यादिफलनिःस्पृहः १८ ।

sanskrit

Brahmā said: The attainment of Śiva’s region is the Achievable. Means of achievement is the service rendered unto Him. Sādhaka (the performer of the rite) is the person who is free from desire even for permanence which attitude is the result of His grace.

english translation

brahmovAca | sAdhyaM zivapadaprAptiH sAdhanaM tasya sevanam | sAdhakastatprasAdAdyo'nityAdiphalaniHspRhaH 18 |

hk transliteration by Sanscript