The Templars were pretty fearless and thus fought with the utmost ferocity in battle, if you saw those guys charging you totally oblivious to the arrows your firing at them and crashing into your line then I think you'd be afraid. To avoid being overwhelmed by archers the Templars would wait behind the infantry and choose their time to charge carefully.
Its psychological as much as anything else, their clothing the brilliant white blazened with a red cross made them stand out a mile away and would of been a tremendous sight on the battlefield. They never seemed to fear death and would make outrageous charges against much larger forces and would often cost many lives to take them down.
http://www.ordotempli.org/knights_templar_armour_research1.h tm