Shabbat 86A

כטבלא מרובעת. כטבלא הוא דשרי, הא לאו הכי ⁠— אסור! התם לאקולי בה קולא אחרינא, להתיר ראש תור היוצא הימנה.

as a square board. All of the halakhot of planting various species were stated with regard to a square-shaped garden bed. By inference: When it is like a square board, it is permitted; and when that is not the case, it is prohibited. Planting different species in horizontal and vertical rows without a space between the species is ineffective, even with circles. Rav Ashi replied: When the baraita says a square board, it does not mean that the only way to demarcate between different species is when the rows are in that configuration. Rather, it is to introduce a different leniency. The baraita came to permit a triangular plot that protrudes from it into another field. This means that a triangular protrusion into another field is considered a conspicuous demarcation only if the bed was square; in that case, no additional measures are necessary.

מתני׳ מנין לפולטת שכבת זרע ביום השלישי שתהא טמאה? שנאמר: ״היו נכנים לשלשת ימים״. מנין שמרחיצין את המילה ביום השלישי שחל להיות בשבת? שנאמר: ״ויהי ביום השלישי בהיותם כאבים״. מנין שקושרין לשון של זהורית בראש שעיר המשתלח? שנאמר: ״אם יהיו חטאיכם כשנים כשלג ילבינו״. מנין לסיכה שהיא כשתייה ביום הכפורים? אף על פי שאין ראיה לדבר זכר לדבר, שנאמר: ״ותבא כמים בקרבו וכשמן בעצמותיו״.

Mishnah: The Mishnah continues to cite a series of unrelated halakhot based upon biblical allusions. From where is it derived that a woman who discharges semen even on the 3rd day after sex is ritually impure, just like one who touches semen (see Leviticus 15:17)? Because the semen remains fit for insemination, it can transmit impurity, as it is stated prior to the revelation at Sinai: “And he said to the people, prepare yourselves for 3 days, do not approach a woman” (Exodus 19:15). This 3-day separation period ensured that even a woman who discharged semen would be pure. The Mishnah cites another halakha based on a biblical allusion: From where is it derived that one may wash the circumcision on the 3rd day, meaning the 3rd day after the circumcision, even if it occurs on Shabbat? As it is stated: “And it came to pass on the 3rd day when they were in pain” (Genesis 34:25). The pain of circumcision lasts at least 3 days, and as long as the child is in pain he is considered to be in danger. The Mishnah cites another halakha with an allusion in the Bible: From where is it derived that one ties a scarlet strip of wool to the head of the scapegoat that is dispatched to Azazel? As it is stated: “If your sins be like scarlet, they will become white like snow” (Isaiah 1:18). Since the goat is offered to atone for sins, red wool is tied to its horns. The Mishnah cites another allusion. From where is it derived that smearing oil on one’s body is like drinking and is similarly prohibited on Yom Kippur? Although there is no proof for this, there is an allusion to it, as it is stated: “And it comes into his inward parts like water and like oil into his bones” (Psalms 109:18). The verse appears to equate smearing oil on one’s body with drinking water.