III Maccabees 7:9

9 For know ye, that should we conceive any evil design, or in any way aggrieve them, we shall ever have as our opposite, not man, but the highest God, the ruler of all might. From Him there will be no escape, as the avenger of such deeds. Fare ye well.

III Maccabees 7:9 In-Context

7 and taking into consideration their constancy and fidelity towards us and towards our ancestors, we have, as we ought, acquitted them of every sort of charge.
8 And we have dismissed them to their several homes; bidding all men everywhere to do them no wrong, or unrighteously revile them about the past.
9 For know ye, that should we conceive any evil design, or in any way aggrieve them, we shall ever have as our opposite, not man, but the highest God, the ruler of all might. From Him there will be no escape, as the avenger of such deeds. Fare ye well.
10 When they had received this letter, they were not forward to depart immediately. They petitioned the king to be allowed to inflict fitting punishment upon those of their race who had willingly transgressed the holy god, and the law of God.
11 They alleged that men who had for their bellies' sake transgressed the ordinances of God, would never be faithful to the interests of the king.

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