Make For Yourself Flint Knives and the Holy Tongue of Torah

"Make for yourself flint knives" (Joshua 5:2). Rabbi Ami said: In four places the expression "make for yourself" is stated. In three it was explained, and in one it was not explained. "Make for yourself an ark of gopher wood" (Genesis 6:14) was explained - beams of kadrodos (cedar). "And make for yourself flint knives" was explained - blades of rock. "Make for yourself two trumpets of silver" (Numbers 10:2) was explained. "Make for yourself a fiery serpent" (Numbers 21:8) was not explained. Rabbi Yudan in the name of Rabbi Yose: "A wise man will hear and increase learning" (Proverbs 1:5) - this is Moses, who said: If I make it of gold, this word does not fall upon that word; if I make it of silver, this word does not fall upon that word. Behold, I will make it of copper (nechoshet). Why? Because this word falls upon that word, as it is said, "and Moses made a serpent of copper (nachash nechoshet)" (Numbers 21:9). From here we learn that the Torah was given in the holy tongue.