Mishnayos Keilim Perek 1 Mishnah 4

שהיא מטמאה את בועלה – seven [days] of uncleanness. For regarding a menstruating woman, it is written (Leviticus 15:24): “[And if a man lies with her,] her menstrual impurity is communicated to him and he shall be impure seen days” and it is also written regarding a woman with flux (Leviticus 15:25): “she shall be impure, as though at the time of her menstrual impurity, as long as her discharge lasts,” and we expound upon "תהיה טמאה היא"/she shall be impure – to include the man who had sexual intercourse with her. [The word] "היא"/she – that she defiles the man who had sexual intercourse with her but the person with gonorrhea does not defile whomever he has had sexual intercourse with for [a period of] seven [days], but only the defilement of contact/touching and carrying.

למעלה מן הזבה מצורע – a leper [defiles] by lying and sitting like a woman with a flux. But more stringent than her, he defiles through entering [a place]. When he comes to the house, everything that is in the house is impure, even though he did not touch it/come in contact with it, as it is written (Leviticus 13:46): “[He shall be impure as long as the disease is upon him. Being impure, he shall dwell apart;] his dwelling shall be outside the camp,” which teaches that is dwelling is impure. From here, they (i.e., the Rabbis) stated that a leper that sits underneath the tree and a pure person passes by, the pure person is defiled. But if a pure person sits underneath the tree and a leper passes by, the pure person is not defiled. And similarly leprous clothing and with a leprous stone. And especially concerning a leper during the days of his receiving final judgment following probationary enclosure, but during the days of his counting, that is, after shaving/cutting off all of his hair and [the offering of] the birds, he does not defile by entering and he does not defile by lying and sitting.

למעלה מן המצורע עצם כשעורה שהוא מטמא טומאת שבעה – as it is written (Numbers 31:24): “On the seventh day you shall wash your clothes and be pure, [and after that you may enter the camp],” all defilements that you become defiled through [contact with] the dead will not be less than seven [days]. But even though that the leper is more stringent than a bone the size of a barley corn, for the leper defiles everything that is in the tent when he comes to the tent, but the bone the size of barley corn does not defile in the tent, nevertheless, on this level, however, the bone the size of a barley corn is more stringent as it defiles an uncleanness of seven[days]. And similarly, all of these are of [increasingly] higher levels that are considered not for every matter it is stated that the second is more stringent than the first, for many of them have a stringency in the first [mentioned] that is not [found] in the second, but for that [higher] level that he counts alone it is stated that the second is more stringent.

חמור מכולם מת – there are those of them [listed] that are more stringent than a corpse, for a man with gonorrhea and a woman with flux makes [defilement] through lying and sitting and defile with the very heavy stone, but a corpse does not [defile] through lying and sitting and doesn’t defile with a very heavy stone. But nevertheless, on this [higher] level, a corpse is more stringent than all of them, as it defiles by overshadowing. For just as a leper causes defilement through entrance, his defilement is not like the defilement of overshadowing, for if he brought his hand into a leprous house, it is pure, and even if he completely entered except for his nose, he is pure, for partial entering is not called entering. And even a partition saves in a house where the leper is, as is taught in the Mishnah of [Tractate] Negaim at the end of the thirteenth chapter [Mishnah 12]: “If he entered the synagogue, they make a partition for him ten handbreadths high [by four cubits wide]. He enters first and leaves last.” And all in a similar manner concerning a corpse that defiles in a tent. Alternatively, there is a division between a sitting leper and a passing leper, as I have explained above, what is not the case regarding a corpse.