Nazir 41b (מא:) — the Talmud in English

And if

the Torah had written

“his head”

alone

and had not written “his beard,” it might have been assumed

[I would have said]:

Although

it indicates

from “his head”

two things

[even though the two following laws can be derived from “his head”]:

1.

A positive mitzva comes and overrides a negative commandment,

just as the shaving of a metzora overrides the prohibition against surrounding the head.

2.

It also indicates

further

that

“the shaving of the entire head is called surrounding”—

and

however

still

the shaving of a metzora, which is

with a razor

specifically,

from where do we know this!?

For this reason the Torah wrote

“his beard,” from which we learn that the shaving of the metzora is specifically with a razor, as was explained earlier in the Gemara.

And the Gemara further explains:

And Rabbi Eliezer,

who derives from “his head” that the nazirite metzora shaves his head with a razor,

that a positive mitzva overrides a negative commandment [from this verse the Sages learn that a positive mitzva overrides a negative commandment]—

from where does he derive it

as it is taught:

It is stated in the Torah:

“You shall not wear shatnez,”

wool and linen together. “You shall make for yourself twisted threads on the four corners of the garment with which you cover yourself”; and for this reason the passage concerning tzitzit was juxtaposed to that concerning shatnez

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