Either Party may, by Leave of the Court or a Judge, plead and demur to the same Pleading at the same Time, upon an Affidavit by such Party, or his Attorney, if required by the Court or Judge, to the Effect that he is advised and believes that he has just Ground to traverse the several Matters proposed to be traversed by him, and that the several Matters sought to be pleaded as aforesaid by way of Confession and Avoidance are respectively true in Substance and in Fact, and that he is further advised and believes that the Objections raised by such Demurrer are good and valid Objections in Law, and it shall be in the Discretion of the Court or a Judge to direct which Issue shall be first disposed of.