Jamieson, Fausset and Brown on 2 Chronicles 35:12

12. they removed the burnt offerings--Some of the small cattle being designed for burnt offerings were put apart by themselves, that they might not be intermingled with the paschal lambs, which were carefully selected according to certain rules, and intended to be sacramentally eaten; and the manner in which those burnt offerings were presented seems to have been the following: "All the subdivisions of the different fathers' houses came one after another to the altar in solemn procession to bring to the priests the portions which had been cut off, and the priests laid these pieces upon the fire of the altar of burnt offering."