6And Yehovah sent among the people the burning serpents, and they bite the people, and much people of Israel die; 7and the people come unto Moses and say, ‘We have sinned, for we have spoken against Yehovah, and against you; pray unto Yehovah, that He turn aside from us the serpent;’ and Moses prayed on behalf of the people. 8And Yehovah said unto Moses, ‘Make for thee a burning [serpent], and if the serpent has bitten any man, and he looks expectantly unto the serpent of brass — he shall live. 9And Moses makes a serpent of brass, and sets on the ensign, and if the serpent has bitten any man, and he looks expectantly unto the serpent of brass — he shall live.
The Hebrew word for serpent is - שָׂרָף saraph - Usage: AV - fiery serpent 3, fiery 2, seraphim 2; 7 נָחָשׁ nachash - ) serpent, snake 1a) serpent
6 And the bath-kol fell from the high heaven, and thus spoke: Come, all men, and see all the benefits which I have done to the people whom I brought up free out of Mizraim. I made manna come down for them from heaven, yet now turn they and murmur against Me. Yet, behold, the serpent, whom, in the days of the beginning of the world, I doomed to have dust for his food, hath not murmured against me: but My people are murmuring about their food. Now shall the serpents who have not complained of their food come and bite the people who complain. Therefore did the Word of the Lord send the basilisk serpents, and they bit the people, and a great multitude of the people of Israel died. (Num. 21:6 PJE)
bath-kol - In the Abrahamic religions, the voice of God is a communication from God to human beings, heard by humans as a sound with no apparent physical source. In rabbinic Judaism, such a voice was known as a bat kol, and was a "heavenly or divine voice which proclaims God's will or judgment."
basilisk - In European bestiaries and legends, a basilisk is a legendary reptile reputed to be a serpent king, who can cause death with a single glance.
LXX - 6 And the Lord sent among the people deadly serpents, and they bit the people, and much people of the children of Israel died.
7 And the people came to Moses and said, We have sinned, for we have spoken against the Lord, and against thee: pray therefore to the Lord, and let him take away the serpent from us.
8 And Moses prayed to the Lord for the people; and the Lord said to Moses, Make thee a serpent, and put it on a signal-staff; and it shall come to pass that whenever a serpent shall bite a man, every one so bitten that looks upon it shall live.
9 And Moses made a serpent of brass, and put it upon a signal-staff: and it came to pass that whenever a serpent bit a man, and he looked on the brazen serpent, he lived. (Num. 21:6-9 LXE)