If on the trial of any person convicted of any crime any question of difficulty in point of law shall have arisen it shall be lawful for the judge, in his discretion, to reserve such question of law for the consideration and determination of the Court of Criminal Appeal, and in any such case to respite the execution of the judgment on such conviction, or postpone the judgment until such question of law shall have been considered and determined; and in either case the judge, in his discretion, shall commit the person convicted to gaol, or shall admit the convicted person to bail in order to secure that he shall appear at such time and place as the judge shall direct, and receive judgment, or render himself in execution, as the case may be.