p. 240
‘कर्मोदये’ इत्यादिना नित्यानां काम्यानां च पितृलोकादिप्राप्तिहेतुत्वेन संसारानर्थहेतुत्वस्य दर्शितत्वात् प्रतिषिद्धस्य कर्मणः नरकहेतुत्वेनानर्थहेतुत्वस्य दर्शितत्वात् न वेदा वेदविदं त्रातुं शक्ताश्चेत्, अथ कस्मात् हेतोः अयं प्रलापः सना
In plain words
The passage beginning 'when action arises' has already shown it: the obligatory rites and the rites done for a wish both lead to the world of the ancestors and realms like it, and so they are causes of the whole calamity of saṃsāra. It has shown too that forbidden action causes harm, since it leads to hell. So if the Vedas cannot rescue the man who knows the Vedas — then on what ground is this said at all, this idle talk, the ancient...
Close to the Sanskrit
Since by the passage beginning 'karmodaye' and what follows, the being-a-cause-of-the-calamity-of-saṃsāra of the obligatory and the desire-prompted rites has been shown, through their being the cause of attaining the world of the ancestors and the rest; and since, of prohibited action, the being-a-cause-of-harm has been shown through its being the cause of hell — if the Vedas are not able to rescue the knower of the Veda, then for what reason is this idle talk, the ancient...