An usefull case of conscience, discussed, and resolved [electronic resource] : Concerning associations and confederacies with idolaters, infidels, hereticks, or any other known enemies of truth and godlinesse. / By Mr George Gillespie, late minister at Edinburgh. Whereunto is subjoyned a letter written by him to the commissioners of the Generall Assembly, in the time of his sicknesse; Together with his testimony unto this truth, written by him two dayes before his death.