atha prāgasamarthaḥ sahakārikāraṇayogāt paścāt samartho bhavatītyabhyupeyate, tadā jahatu bhavanto vede nityatāśām //
If it is accepted that [something] previously inefficient later becomes efficient through connection with auxiliary causes, then you [plural] should abandon [your] hope for the eternality of the Veda!