Eruvin 21A

מטפס ועולה מטפס ויורד.

must climb up and climb down into the well, and drink there.

איני? והאמר רב יצחק אמר רב יהודה אמר שמואל: לא הותרו פסי ביראות אלא לבאר מים חיים בלבד. ואי לבהמה, מה לי חיים מה לי מכונסין? בעינן מידי דחזי לאדם.

The Talmud raises a difficulty: Is that so? Is the allowance of upright boards for animals alone? Didn’t Rav Yitzḥak say that Rav Yehuda said that Shmuel said: Upright boards surrounding wells were permitted only where the wells contain potable, running spring water? If the allowance is only for animals, what is the difference to me if it is spring water and what is the difference to me if it is collected water? Granted, collected water is inferior to spring water, but it is still suitable for animals to drink. The Talmud answers: We require something that is fit for humans.

גופא: לא הותרו פסי ביראות אלא לבהמה בלבד, אבל אדם מטפס ועולה מטפס ויורד. ואם היו רחבין, אפילו לאדם נמי. ולא ימלא אדם מים ויתן לפני בהמתו, אבל ממלא הוא ושופך לפני בהמה ושותה מאיליה.

The Talmud examines the baraita cited in the course of the previous discussion. Returning to the matter itself, the statement quoted above: Upright boards surrounding wells were permitted only for cattle, but a person must climb up and climb down into the well and drink there. But if the wells were too wide for him to climb, they are permitted for a person as well. A person may not fill a bucket with water and hold it before his animal on Shabbat, but he may fill it and pour it out before the animal into a trough, and the animal drinks of its own accord.

מתקיף לה רב ענן: אם כן, מה הועילו פסי ביראות? מה הועילו?! למלאות מהן!

Rav Anan strongly objects to this explanation: If so, what purpose do the boards surrounding a well serve? The Talmud immediately expresses its surprise: How can he ask what purpose do they serve? They allow people to draw water from the wells, which would otherwise be prohibited.