A.T. Robertson Commentary Acts 28:4

"And when the barbarians saw the [venomous] creature hanging from his hand, they said one to another, No doubt this man is a murderer, whom, though he hath escaped from the sea, yet Justice hath not suffered to live." — Acts 28:4 (ASV)

The beast (το θηριον). Diminutive of θηρ and so little beast. See on Mr 1:13. Aristotle and the medical writers apply the word to venomous serpents, the viper in particular (Knowling), as Luke does here. Vincent calls attention to the curious history of our word "treacle" for molasses (Latin theriaca) from θηριακη, an antidote made from the flesh of vipers. Coverdale translates Jer 8:22 "There is no more treacle in Gilead." Jeremy Taylor: "We kill the viper and make treacle of him."

Hanging from his hand (κρεμαμενον εκ της χειρος αυτου). Vivid picture of the snake dangling from Paul's hand. Present middle participle of κρεμαμα, late form for κρεμαννυμ, to hang up, to suspend (cf. Galatians 3:13).

No doubt (παντως). Literally, By all means, old adverb. Cf. 21:22; Luke 4:23; 1 Corinthians 9:22. Only by Luke and Paul in the N.T. "They knew that he was a prisoner being taken to Rome on some grave charge, and inferred that the charge was murder" (Page).

Though he hath escaped (διασωθεντα). First aorist passive participle of διασωζω (same verb used in 24:43,44; 28:1), so-called concessive use of the participle (Robertson, Grammar, p. 1129).

Yet Justice (δικη). An abstraction personified like the Latin Justitia (Page). The natives speak of Δικη as a goddess, but we know nothing of such actual worship in Malta, though the Greeks worshipped abstractions as in Athens.

Hath not suffered (ουκ ειασεν). Did not suffer. They look on Paul as a doomed man as good as dead. These people thought that calamity was proof of guilt, poor philosophy and worse theology.