Sotah 28b — the Talmud in English

And from the place from which you came,

since we learned the law of the creeping creature only from Sotah, we now return and reason that only when the Sotah is impure as a matter of doubt are the pure things also impure as a matter of doubt.

What

just as in

a Sotah,

it is spoken of in

the private domain,

which is the place suitable for seclusion,

so too a creeping creature,

only in

the private domain

is its doubt impure; but if a doubt of impurity occurred in the public domain, it is pure.

And what of a Sotah

is she

a matter that has awareness with which to ask,

for it is possible to ask the woman whether she became impure or not,

so too a creeping creature

specifically

a matter that has awareness with which to ask,

for the subject under discussion is a person, concerning whom it is doubtful whether he touched a creeping creature, or pure things with which a person was occupied when the doubt arose whether they touched a creeping creature; it is possible to ask the person whether he touched [it] or not, and if he says that he does not know, they are impure as a matter of doubt.

And from here they said: A matter that has awareness with which to ask

and it stands

in the private domain, its doubt is impure.

But if it is

in the public domain, its doubt is pure.

And one that has no awareness with which to ask,

such as a dead creeping creature that was passed beside the pure things, and it is doubtful whether it touched them or not, for it is impossible to ask the pure things whether they touched it or not,

whether in the private domain or in the public domain, its doubt is pure.

And we raised [the following] against it:

And Rabbi Yishmael,

who said to Rabbi Akiva in the beraita that a verse is not needed to disqualify the Sotah who secluded herself from the priesthood, for we know this by a kal va-chomer, [the following] is difficult:

Rabbi Akiva said: teruma,

for he expounds “and she became impure” to disqualify her from teruma, and he did not speak at all about the priesthood,

and he [Rabbi Yishmael] answers him,

Rabbi Yishmael,

“The priesthood?!”

And furthermore

there is a difficulty:

For Rabbi Akiva, from where does he know the priesthood,

that she is forbidden to marry a priest?

And it is impossible to say that he indeed permits her with regard to the priesthood, for there is a kal va-chomer from teruma, which is forbidden.

And it is also impossible to say that he truly forbids her because of the kal va-chomer, that is, [that this is] Rabbi Yishmael?

And if you would say

Rabbi Akiva held

the priesthood does not require a verse

to forbid [her],