विद्याऽविनाशे जन्मविनाशः
In plain words
When is not destroyed, birth is destroyed.
The commentators
Śivasūtra with Kṣemarāja's Vimarśinī
न चैवं स्वशक्तिनिर्मितभूतभावशरीरवतोऽस्य जन्मादिबन्धः कश्चिदित्याह - विद्याऽविनाशे जन्मविनाशः ॥ १८ ॥ प्रोक्तायाः सहजविद्याया अविनाशे सततोन्मग्नतया स्फुरणे जन्मनः अज्ञानसहकारिकर्महेतुकस्य दुःखमयस्य देहेन्द्रियादिसमुदायस्य नाशो विध्वंसः संपन्न एव । यदुक्तं श्रीकण्ठ्याम् सप्रपञ्चं परित्यज्य हेयोपादेयलक्षणम् । तृणादिकं तथा पर्णं पाषाणं सचराचरम् ॥ शिवाद्यवनिपर्यन्तं भावाभावोपबृंहितम् । सर्वं शिवमयं ध्यात्वा भूयो जन्म न प्राप्नुयात् ॥ इति । श्रीस्वच्छन्दे स्वनिर्वाणं परं शुद्धं गुरुपारम्परागतम् । तद्विदित्वा विमुच्येत गत्वा भूयो न जायते ॥ इति । श्रीमृत्युजित्यपि तत्त्वत्रयविनिर्मुक्तं शाश्वतं त्वचलं ध्रुवम् । दिव्येन योगमार्गेण दृष्ट्वा भूयो न जायते ॥ इति ॥ १८ ॥
In plain words
When knowledge does not perish, birth perishes. And though he has, in this way, bodies of elements and of states created by his own power, there is no bondage at all of birth and the rest for him. So he says: When the innate knowledge described does not perish, that is, when it shines forth, ever emerged, the perishing, the destruction, of birth is indeed accomplished: of the assemblage of body, senses and the rest, made of suffering, caused by karma that has ignorance as its helper. As the Śrīkaṇṭhī says: "Leaving aside, with its whole spread, what is marked as to be rejected or accepted, grass and the like, a leaf, a stone, all that moves and does not move, from Śiva down to earth, swelled by being and non-being: meditating on all as made of Śiva, he would not come to birth again." The Svacchanda: "His own nirvāṇa, supreme, pure, come down through the line of gurus: knowing that, he is freed, and having gone there, is not born again." And the Mṛtyujit too: "Free of the three tattvas, eternal, unmoving, steadfast: seeing it by the divine path of yoga, he is not born again."