His knees went water/ to pass water from fear

He was frightened and lost his composure. He was afraid and confused. “Water was poured over his legs.” “He did it in his pants” (original meaning: he urinated or sweated from great fear; alternatively: his knees melted like water. Figuratively: he grew weak).

(“All hands shall grow weak, and all knees shall run with water.” — Ezekiel 7:17. “And see how much the Omnipresent is concerned for human dignity: because of the one who is fearful and faint-hearted — when he returns, they say, ‘Perhaps he built a house, perhaps he planted a vineyard, perhaps he betrothed a wife.’ All of those were required to bring proof, except for the one who is fearful and faint-hearted, whose proof is with him: he hears the sound of shields clashing and is terrified; the sound of horses neighing and trembles; the blast of horns and is alarmed; he sees swords being drawn — and water runs down between his knees.” — Sifrei Devarim, Parashat Shoftim, section 178.)

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