Bhashya
पृष्ट प्राण इति ह उवाच, युक्त प्रस्तावस्य प्राणो देवतेति ।कथम् ? सर्वाणि स्थावरजङ्गमानि भूतानि प्राणमेवअभिसविशन्ति प्रलयकाले, प्राणमभि लक्षयित्वा प्राणात्मनैवोज्जिहते प्राणादेवोद्गच्छन्तीयथ उत्पत्तिकाले, अत सैषादेवता प्रस्तावमन्वायत्ता, ता चेदविद्वान् त्व प्रास्तोष्यप्रस्तवन प्रस्तावभक्तिं कृतवानसि यदि, मूर्धा शिर ते व्यप-तिष्यत् विपतितमभविष्यत् तथोक्तस्य मया तत्काले मूर्धाते विपतिष्यतीति ।अतस्त्वया साधु कृतम्, मया निषिद्धकर्मणा यदुपरममकार्षीरित्यभिप्राय ॥
In plain words
When asked about prāṇa, he said: 'Prāṇa is indeed the fitting deity for the prastāva.' Why? Because at the time of dissolution, all moving and stationary beings merge completely into prāṇa, and at creation they emerge from prāṇa as living breath. Therefore that deity is anchored to the prastāva. Had you chanted it without knowing her, your head would have split apart. Since you stopped when I prohibited you, you acted wisely.
Close to the Sanskrit
When asked 'prāṇa', he spoke: 'Prāṇa is appropriate as the deity of the prastāva.' How? All unmoving and moving beings merge into prāṇa alone at dissolution, and rising up with the nature of prāṇa, they spring forth from prāṇa at creation. Therefore that deity is anchored to the prastāva; if you without knowing her had chanted the prastāva, your head would have shattered... Therefore it is well done by you that you brought about cessation from the prohibited action, this is the intent.