וַיָּקִ֨ימוּ עָלָ֜יו גַּל־אֲבָנִ֣ים גָּד֗וֹל עַ֚ד הַיּ֣וֹם הַזֶּ֔ה וַיָּ֥שָׁב יְהוָ֖ה מֵחֲר֣וֹן אַפּ֑וֹ עַל־כֵּ֠ן קָרָ֞א שֵׁ֣ם הַמָּק֤וֹם הַהוּא֙ עֵ֣מֶק עָכ֔וֹר עַ֖ד הַיּ֥וֹם הַזֶּֽה׃ (פ)
E innalzarono sopra di lui un grande mucchio di pietre, che è là fino a questo giorno; e il Signore si ritrasse dall'ardore della sua ira. Perciò il nome di quel luogo fu chiamato valle di Acor, fino a questo giorno.
English Explanation of Mishnah Oholot
[With regard to] a house filled with earth or pebbles which he [decided] to leave there, or similarly a heap of produce or a mound of pebbles even such as Akhan's mound, and even if the uncleanness is by the side of the vessels, the uncleanness cleaves upwards and downwards. The mishnah discusses three situations: 1) Someone's house is full of pebbles or earth and he decided not to remove them. 2) A heap of produce that is found outside of a house. 3) A mound of stones, even if it is like the stones that were put on top of Akhan when he was executed (see Joshua 7:26). In all of these cases there is a source of impurity within the mound (or house) but it is not touching the vessels. The mishnah rules that the impurity goes up and down but does not defile the vessels. In other words, the impurity is not found in an ohel, and therefore it doesn't spread to the sides.
German Commentary
selbst wie der Steinhäufen über ’Achan. Vgl. Jos. 7, 26. Gemeint ist, selbst wenn der Haufen so gross ist, wie jener Steinhaufen. Nach רא״ש soll es bedeuten: Selbst wenn er, wie der Steinhaufen von ’Achan, nur auf kurze Zeit errichtet war. – Allein bereits יו״ב bemerkt, dass es dort heisst עד היום הזה; der Steinhaufen bestand also lange Zeit.