Quoting Commentary for Ezekiel 47:2

וַיּוֹצִאֵנִי֮ דֶּֽרֶךְ־שַׁ֣עַר צָפוֹנָה֒ וַיְסִבֵּ֙נִי֙ דֶּ֣רֶךְ ח֔וּץ אֶל־שַׁ֣עַר הַח֔וּץ דֶּ֖רֶךְ הַפּוֹנֶ֣ה קָדִ֑ים וְהִנֵּה־מַ֣יִם מְפַכִּ֔ים מִן־הַכָּתֵ֖ף הַיְמָנִֽית׃

Then brought he me out by the way of the gate northward, and led me round by the way without unto the outer gate, by the way of the gate that looketh toward the east; and, behold, there trickled forth waters on the right side.

Bartenura

מים מפכים – as it is written in Ezekiel (47:2): “And I found water was gushing from [under] the south wall,” and that is south which is called “right-hand,” as it is written )Psalms 89:13): “North and south – [You created them; Tabor and Hermon sing forth Your name].” But see Ezekiel in prophecy that they would go out from the House of the Holy of Holies thin like the proboscides of locusts (see Tractate Pesahim, Chapter 3, Mishnah 5), and when they would arrive at this gate, they would grow strong/gather courage and become like the fulness of a small flask/jar and that is why they call them “gushing waters.”
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