Notes by Rabbi Yehoshua Hartman on Netivot Olam, Netiv Hatorah 14:186פירושים והערות מהרב יהושע הרטמן על נתיבות עולם, נתיב התורה י״ד:קפ״ו
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Numbers 21:8במדבר כ״א:ח׳
And the Lord said to Moshe, Make thee a venomous serpent, and set it upon a pole: and it shall come to pass, that every one that is bitten, when he looks upon it, shall live.
Rashi on Numbers 21:8:2רש"י על במדבר כ״א:ח׳:ב׳
כל הנשוך ANYONE THAT IS BITTEN — even though a dog or ass had bitten him, he felt the effects of the injury and became enfeebled more and more (cf. Tanchuma); only that the bite of a serpent kills more speedily. On this account it is stated here: וראה אתו, “whoever has been bitten, when he seeth it, [shall live]” — a mere glance sufficed to heal him. But in the case of the serpent’s bite it is stated והביט, and he gazed — “and it came to pass that if a serpent had bitten any man, when he gazed [at the brazen serpent, he lived]”, for the serpent’s bite was not so quick to heal unless he gazed intently (cf. Jerusalem Talmud Rosh Hashanah 3:9). — Our Rabbis said: But could the copper serpent cause death or life?! But the explanation is that when the Israelites in gazing at the serpent looked up on high and subjected their hearts to their Father in Heaven, they were healed, but if they did not do this they waste away (Rosh Hashanah 29a).
Gur Aryeh on Bamidbar 21:8:3גור אריה על במדבר כ״א:ח׳:ג׳
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Netivot Olam, Netiv Hatorah 14:25נתיבות עולם, נתיב התורה י״ד:כ״ה
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