G2191–ἔχιδνα–echidna

But when he saw many of the Pharisees and Sadducees coming for baptism, he exclaimed, "O vipers' brood, who has warned you to flee from the coming wrath?

ἐχιδνῶν, echidnōn “of vipers,”

O vipers' brood, how can you speak what is good when you are evil? For it is from the overflow of the heart that the mouth speaks.

ἐχιδνῶν, echidnōn “of vipers,”

O serpents, O vipers' brood, how are you to escape condemnation to Gehenna?

ἐχιδνῶν, echidnōn “of vipers!”

Accordingly John used to say to the crowds who came out to be baptized by him, "O vipers' brood, who has warned you to flee from the coming wrath?

ἐχιδνῶν, echidnōn “of vipers,”

Now, when Paul had gathered a bundle of sticks and had thrown them on the fire, a viper, driven by the heat, came out and fastened itself on his hand.

ἔχιδνα echidna “a viper”