[Heb., ʼeph·ʽehʹ; tsiph·ʽo·niʹ; Gr., eʹkhi·dna].

A poisonous snake equipped with highly specialized fangs that can be tilted back against the roof of the mouth when they are not being used. The venom of vipers varies according to types, several of which exist in Palestine. One of the most dangerous is the sand viper (Vipera ammodytes) of the Jordan Valley. Another kind is the Palestine viper (Vipera palaestina). The Hebrew ʼeph·ʽehʹ is commonly connected with the Arabic ʼafʽan, which refers to the carpet viper, a poisonous snake of the sandy Jericho plains.

The potency of the viper’s poison is alluded to at Job 20:16, where Zophar speaks of “the tongue of a viper” as having the power to kill. Shipwrecked on the island of Malta, the apostle Paul was collecting a bundle of sticks and laying them upon a fire when a viper came out and fastened itself on Paul’s hand. However, Paul “shook the venomous creature off into the fire and suffered no harm,” though the people standing by expected Paul to swell up with inflammation or suddenly die.​—Ac 28:3-6.

Illustrative Use. The dangerous bite of the viper is used in an illustrative way at Proverbs 23:32, where the wise man describes the effects of the excessive use of wine, saying: “It bites just like a serpent, and it secretes poison just like a viper [Heb., u·khetsiph·ʽo·niʹ].” Describing the wickedness that God’s people Israel had come to practice, the prophet Isaiah wrote: “The eggs of a poisonous snake are what they have hatched . . . Anyone eating some of their eggs would die, and the egg that was smashed would be hatched into a viper.” (Isa 59:5) Most snakes lay eggs, and while the majority of the vipers are not oviparous (egg laying), certain types are.

John the Baptizer called the Pharisees and Sadducees “offspring of vipers.” (Mt 3:7; Lu 3:7) And Jesus Christ called the scribes and Pharisees “offspring of vipers” because of their wickedness and the deadly spiritual harm they could inflict upon unsuspecting persons.​—Mt 12:34; 23:33.