The following is an excerpt from Westminster divine George Gillespie's piece, Forbidden Alliances Concerning Associations and Confederacies with Idolaters, Infidels, Heretics, or Any Other Known Enemies of Truth and Godliness:
The law is also to be applied against civil covenants, not of peace or of commerce, but of war; that is, a league offensive and defensive, wherein we associate ourselves with idolaters, infidels, heretics, or any other known enemies of truth or godliness, so as to have the same friends or enemies. A covenant of peace or commerce with such may happen to be unlawful in respect of some circumstances, as when peace is given to those rebels, murderers, incendiaries in the kingdom, who, by the law of God, ought to be destroyed by the hand of justice; or when commerce with idolaters is so abused, as to furnish them with the things that they are known to make use of in their idolatry. But as for [Gk.] summaxia, a confederacy engaging us into a war with such associates, it is absolutely, and in its own nature, unlawful; and I find it condemned by good writers of the popish party, of the Lutheran party, and of the orthodox party. Some of all these are before cited.