“You brood of vipers!
How can you speak
Good things,
When you are evil?
Out of the abundance
Of the heart,
The mouth speaks.”
γεννήματα ἐχιδνῶν, πῶς δύνασθε ἀγαθὰ λαλεῖν πονηροὶ ὄντες; ἐκ γὰρ τοῦ περισσεύματος τῆς καρδίας τὸ στόμα λαλεῖ.
This saying seems to be unique to Matthew. Earlier in this work, he had John the Baptist call the Pharisees and Sadducees a blood of vipers or snakes in chapter 3:7. In chapter 23:33, once again he referred to the Scribes and Pharisees as vipers or snakes. Was he referring to the Pharisees here? Jesus addressed these people as a brood or offspring of vipers or snakes (γεννήματα ἐχιδνῶν). How could they speak good things (πῶς δύνασθε ἀγαθὰ λαλεῖν), when they were evil (πονηροὶ ὄντες)? Their mouths spoke (τὸ στόμα λαλεῖ) out of the abundance or overflow of their hearts (ἐκ γὰρ τοῦ περισσεύματος τῆς καρδίας). They could not fool anyone. Their evil hearts showed up in their speech, even if they tried to be good.
Eugene Finnegan Bible Project 