Mishnayos Keilim Perek 1 Mishnah 1

אבות הטומאה. השרץ – there are eight reptiles that are written in the [Torah] portion of Shemini (Leviticus 11:29-30): החלד/the mole and עכבר/the mouse [and the צב/lizard; the ענקה/gecko; the כח/land crocodile; the לטאה/lizard; the חמט/sand lizard and the תנשמת/chameleon],” they are the primary sources of ritual impurity to defile humans and utensils/vessels that come in contact with them when they are dead. And their measurements for defiling is like that of a lentil (though we are informed in Tractate Kelim, Chapter 17, Mishnah 8, that whenever a lentil is spoken of, it means…the Egyptian lentil). For the sand lizard/חמט at the beginning of its creation is like that of lentil (see Tractate Nazir 52a). But the limbs have no measure, for even less that of a lentil of a reptile defiles (see Tractate Ohalot, Chapter 1, Mishnah 7). And especially when it is moist, the reptile defiles, but it does not defile when dry, as it is written (Leviticus 11:32): “And anything on which one of them falls when dead [shall be impure: be it any article of wood, or a cloth, or a skin, or a sack – any such article that can be put to use shall be dipped in water, and it shall remain impure until evening; then it shall be pure],” similar to their being dead (see Tractate Niddah 56a).

ושכבת זרע – Specifically the semen of an adult Israelite , but that of a heathen does not defile, even according to the Rabbis, for the nocturnal pollution of a heathen is completely pure. And similarly, the semen of a minor also does not defile, as it is written (Leviticus 15:16): “When a man has an emission of semen, [he shall bathe his whole body in water and remain impure until evening],” a man/איש, but not a minor/קטן who is younger than nine-years and one-day old, for [prior to the age of nine-years and one-day] his act of sexual intercourse is not coition. And its measurement to the observer is a little bit, even similar to a mustard seed, and to contact/touching, like that of a lentil. And specifically moist semen that defiles, as it is written (Leviticus 15:16): “[When a man has] an emission of semen/כי תצא ממנו שכבת זרע,” he who is appropriate for emitting semen, for since the teacher of our Mishnah did not consider a בעל קרי/one who experienced a seminal emission (see Leviticus 15:16-18) as one of the primary sources of defilement, we learn from this that it is none other than first degree of ritual defilement, and this is taught at the conclusion of Tractate Zavim (Chapter 5, Mishnah 11), that a person who experienced a seminal emission is like one who came in contact with a reptile, and is not seen as other than first [degree of ritual defilement].

וטמא מת – a person who became defiled through contact with the dead. But utensils/vessels that came in contact with the dead are like the dead itself, and whatever comes in contact with them is made into a primary source of ritual defilement. But utensils/vessels which came in contact with a person who was defiled through contact with the dead or a person who came in contact with utensils/vessels that had been in contact with the dead, they are primary sources of ritual defilement and are defiled for seven days like a person, as is taught in the Mishnah of the first chapter of Ohalot [Mishnah 2]. But earthenware and foods and liquids that came in contact with the dead do not become primary sources of ritual defilement. And especially an Israelite becomes a primary source of ritual defilement when he touched a dead person. But an idolater and similarly a non-viable birth/premature that was born at the age of a month is not susceptible to become ritually impure if he came in contact with the dead.

ומצורע בימי ספרו – A confirmed leper (declared ritually impure by a Kohen. All the laws applying to a quarantined leper apply to a confirmed leper – who must grow his hair long and rend his garments; to purify himself when healed, he must shave all his hair, and bring a special purification offering) and who is fitted for Levitical uncleanness with [his bringing] [two] birds, and cedar wood and hyssop and two scarlet-dyed yarn and shaving, and he sits from outside his tent for seven days and one the eighth [day] brings his sacrifices (see Leviticus 14:8), and on those seven days are called the days of his counting, and he defiles humans, and it is stated “the washing of his clothing “ (“The one to be purified shall was his clothing” – Leviticus 14:8) on the day of final decision [by a Kohen] and it is stated, “the washing of his clothes” on the days of his counting (Leviticus 14:9: “[On the seventh day he shall shave off all his hair…]he shall wash his clothes [and bathe his body in water; then he shall be pure],” just as there he defiles a human being, so here [also] he defiles a human being.

ומי חטאת שאין בהם כדי הזייה – defiles him through contact. But if they have enough in order to sprinkle [of the water of the purification upon the unclean] it defiles even through carrying, to defile humans and clothing, as it is written (Numbers 19:21): “Further, he who sprinkled the water of lustration shall wash his clothes, and whoever touches the water of lustration shall be impure until evening.” But our Rabbis/teachers learned that the person who sprinkles is pure, and the Biblical verse does not come other than to give a measure to the person carrying [the waters of the sin-offering of the Red Heifer] that there must be enough for sprinkling , and the Biblical verse divided between the two kinds of water, to inform you that water where there is enough for sprinkling defiles a person to defile clothing, but where there isn’t enough [water] for sprinkling, it defiles a person to defile food and liquids but not to defile clothing.

וכלי חרס באויר – when his defilement fell in the airspace of an earthenware vessel, whether it touched ,the vessel or whether it did not touch it, the vessel is defiled. But if it the defilement touched the vessel from the outside, it was not defiled by this contact, as it is written (Leviticus 11:33): “And if any of those (i.e., an article of wood, or a cloth, or a skin, or a sack) falls into an earthen vessel, everything inside it shall be impure [and the vessel itself you shall break],” from inside it/within it, it becomes defiled, but it is not defiled from outside of it.

ואינם מטמאין במשא – that all of these primary sources of ritual defilement that are considered here are written concerning them "הנוגע"/someone who comes in contact with them and it is not written: "הנושא"/he who carries them.