Notwithstanding the austerity of the monastic rule [based on the Cistercian reform of the Benedectine Rule], recruits flocked to the new order, which thenceforth comprised four ranks of brethren:
-the knights, equipped like the heavy cavalry of the Middle Ages;
-the serjeants, who formed the light cavalry;
and two ranks of non-fighting men:
-the farmers, entrusted with the administration of temporals;
-and the chaplains, who alone were vested with sacerdotal orders, to minister to the spiritual needs of the order.
From newadvent.org.
