Wisdom 14:31

31 For it is not the power of them by whom they swear: but it is the just vengeance of sinners, that punisheth always the offence of the ungodly.

Wisdom 14:31 In-Context

29 For insomuch as their trust is in idols, which have no life; though they swear falsely, yet they look not to be hurt.
30 Howbeit for both causes shall they be justly punished: both because they thought not well of God, giving heed unto idols, and also unjustly swore in deceit, despising holiness.
31 For it is not the power of them by whom they swear: but it is the just vengeance of sinners, that punisheth always the offence of the ungodly.

The Brenton translation of the Septuagint is in the public domain.