Verses with the word serpents in the Old Testament (6 verses):

Exodus 7:12
For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods.

Numbers 21:6
And the LORD sent fiery serpents among the people, and they bit the people; and much people of Israel died.

Numbers 21:7
Therefore the people came to Moses, and said, We have sinned, for we have spoken against the LORD, and against thee; pray unto the LORD, that he take away the serpents from us. And Moses prayed for the people.

Deuteronomy 8:15
Who led thee through that great and terrible wilderness, wherein were fiery serpents, and scorpions, and drought, where there was no water; who brought thee forth water out of the rock of flint;

Deuteronomy 32:24
They shall be burnt with hunger, and devoured with burning heat, and with bitter destruction: I will also send the teeth of beasts upon them, with the poison of serpents of the dust.

Jeremiah 8:17
For, behold, I will send serpents, cockatrices, among you, which will not be charmed, and they shall bite you, saith the LORD.