וּכְלִי־חֶ֛רֶשׂ אֲשֶׁר־יִגַּע־בּ֥וֹ הַזָּ֖ב יִשָּׁבֵ֑ר וְכָל־כְּלִי־עֵ֔ץ יִשָּׁטֵ֖ף בַּמָּֽיִם׃
Un vaisseau d’argile, touché par celui qui a le flux, sera brisé; un vaisseau de bois, quel qu’il soit, sera nettoyé dans d’eau.
Rashi
וכלי חרס אשר יגע בו הזב AND THE VESSEL OF EARTH THAT HE WHO HATH THE ISSUE TOUCHETH [SHALL BE BROKEN] — One might think that the law applies also if he touched it from outside (its exterior) etc., as it is stated in Torath Cohanim (Sifra, Metzora Parashat Zavim, Section 3 1).
Siftei Chakhamim
This is [when one] causes it to move. Meaning: Its movement to and fro is caused entirely by the zov’s power, because there is no [such thing as] partially moving, only entirely. The reason Scripture uses the expression “touching” for “moving” is to say that touching is compared to moving — just as touching is [accomplished] with his hands from outside, so too, moving is [accomplished] with his hands from outside — to exclude [the case of] a reed [held] in the zov’s body folds. If there was a reed in his body folds and he moved a pure [object with it], it is pure, since the moving is caused only by his hidden parts.
Rav Hirsch
V. 12. וכלי חרש אשר יגע בו הזב וגו׳ Kap. 11, 33 ist bereits bemerkt, daß כלי חרש nur מקבל טומאה מאוירו sei. הסיטו של זב ist der einzige Fall, daß ein כלי חרש auch von außen טמא wird, daher heißt es hier nicht בתוכו, sondern בו; denn im Zusammenhange mit dem vorigen Verse ist auch diese ישבר .(ת׳׳כ) היסט :נגיעה (siehe Kap. 11, 33). ישטף במים ist ebenso wie טבילה :יכבס בגדיו.