Mishnayos Keilim Perek 8 Mishnah 10

מגע טמא מת – a person who came in contact with something defiled by the dead and becomes first [degree of ritual impurity], that the person defiled through contact with the dead is a primary source of ritual impurity and makes the individual who has contact first [degree of ritual impurity], and liquids and foods that are in his mouth defile the oven when they entered into its airspace. But even though he himself does not defile them, for a vessel does not become susceptible to receive ritual impurity other than from a primary source of ritual impurity. Behold this person states: “what rendered you unclean did not defile me, but you defiled me,”(see also Tractate Kelim 8:4)) as it is taught in the Mishnah in Tractate Parah ]Chapter 8, Mishnayot 2-7], that the Rabbis decreed regarding liquids that they would defile vessels, as a degree because the משקה זב וזבהliquid of a person with gonorrhea/זב and woman suffering from a flux/זבה as was stated in the Tractate Shabbat (which I could not locate. But using the Bar Ilan Responsa Project 25 plus, I was able to locate one mention of a passage with the words"משקה זב וזבה"are found only in Tractate Bekhorot 38a. I stand to be corrected). But the [word] “foods” that is taken here, it (i.e., the Mishnah) refers to it just by the way, without specific reason, for food does not defile a vessel, but only liquids defile vessels. But the closing of his lips does not save [from contracting defilement] for an airtight lid does not save/protect from the defilement that is within from defiling others as is taught in the Mishnah above (see Tractate Kelim, Chapter 8, Mishnah 6), and outside from the law , that which is taught in the Tosefta of Tractate Kelim [Bava Kamma, Chapter 6, Halakha 5]: “Everything affords protection from the power of a clay utensil, even a utensil made of dung or a utensil made of stones or a utensil made of dirt – except for man” (see The Tosefta, Jacob Neusner, Volume 2). Therefore, something pure that food and liquids were inside of its mouth and he brought his head into the airspace of the oven which is [ritually] impure, were defiled. But a man cannot save with an airtight lid from the earthenware vessel/utensil.

בידים מסואבות – hands which are second-degree of ritual impurity and which invalidate the heave-offering/Terumah.

הכניס ידו לתוך פיו – to take the pit that is in his mouth or everything.

ר' מאיר מטמא – the cake of ground figs. For since his hands are unclean/repulsive, the spittle was defiled to become first [degree of ritual impurity] because it is liquid, and the spittle defiled the cake of ground figs, for something that is first-degree [of ritual impurity] makes something else second in non-holy things.

ור' יהודה מטהר – he holds that all the while that the spittle did not leave from the mouth, it is not considered liquid.

ור' יוסי מטמא – that he turned over the cake of ground figs from this side to the other side within his mouth, that the spittle was uprooted. And it purifies without turning it over [in his mouth], whenever it is not uprooted, it is not considered liquid. And the Halakha is according to Rabbi Yossi.