अविज्ञातः पशुस्सो हि सृष्टिधर्मसमाश्रितः ।विज्ञातश्शाश्वतश्शुद्धस्स शिवो नात्र संशयः ॥
In plain words
Not known, he is the paśu, bound to the ways of creation; known, he is everlasting and pure, he is Śiva. Of this there is no doubt.
Word for word
Not known, he indeed the paśu, bound to the ways of creation; known, everlasting, pure, he Śiva; no doubt here.