Reference for Nedarim 7:8

מהו דתימא חידוש הוא שחידשה תורה בנזיר

but even on the view that the shaving is not a bar [to the sacrifices], nevertheless he does not observe the precept of shaving. Mar Zutra the son of R. Mari said: He might violate 'Thou shalt not delay' in respect to his sacrifices. Is this deduced from here; surely, it is rather inferred from elsewhere: [When thou shalt vow a vow unto the Lord, thou shalt not slack to pay it, for the Lord thy God] will surely require it of thee:<span class="x" onmousemove="('comment',' Deut. XXIII, 22. ');">⁷</span>

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