John Calvin Commentary Psalms 58:4

"Their poison is like the poison of a serpent: [They are] like the deaf adder that stoppeth her ear," — Psalms 58:4 (ASV)

Their poison is like the poison of a serpent: they are like the deaf adder. He continues his description; and, though he might have insisted on the fierceness which characterized their opposition, he charges them more particularly, here as elsewhere, with the malicious virulence of their disposition. Some read, their fury; but this does not suit the figure by which they are here compared to serpents.

No objection can be drawn to the translation we have adopted from the etymology of the word, which is derived from heat. It is well known that while some poisons kill by cold, others consume the vital parts by a burning heat. David then asserts of his enemies, in this passage, that they were as full of deadly malice as serpents are full of poison.

To more emphatically express their consummate subtlety, he compares them to deaf serpents, which shut their ears against the voice of the charmer — not the common kind of serpents, but such as are famed for their cunning and are on their guard against every artifice of that description.

But is there such a thing, it may be asked, as enchantment? If there were not, it might seem absurd and childish to draw a comparison from it, unless we suppose David to speak in mere accommodation to mistaken, though generally received, opinion. He would certainly seem, however, to insinuate that serpents can be fascinated by enchantment; and I can see no harm in granting it.

The Marsi in Italy were believed by the ancients to excel in the art. Had there been no enchantments practiced, where was the necessity of their being forbidden and condemned under the Law? (Deuteronomy 18:11). I do not mean to say that there is an actual method or art by which fascination can be effected.

It was doubtless done by a mere sleight of Satan, whom God has suffered to practice his delusions upon unbelieving and ignorant men, although he prevents him from deceiving those who have been enlightened by his word and Spirit. But we may avoid all occasion for such curious inquiry by adopting the view already referred to: that David here borrows his comparison from a popular and prevailing error. According to this view, he is to be understood as merely saying that no kind of serpent was imbued with greater craft than his enemies, not even the species (if such there were) which guards itself against enchantment.