After the Recruitment Drive quest the player became a member of the Temple Knights, however there's been a small problem with the application: You have to be a member of the White Knights of Falador to apply. So to become a member: really help out the white knights, though you already did this in Black Knights' Fortress, you are going to have to do something even more big than stopping a Black Knight invasion.
The main reward for this quest is access to the White Knight's armoury, this armour is about equal to adamant in stats and each piece gives a +1 bonus to prayer. It also contains the only halberd that can be bought outside the elven lands. In order to gain access to all of the equipment, players must rise in the White Knight's ranks. Though if a player of a higher rank first buys the item from the armoury, anybody who has completed the quest can buy it from them and wield it. In order to gain White Knight ranks, players must kill black knights. The best places for this are the Black Knights Fortress and their hangout in the far south part of Taverley Dungeon (Taverley is much preferred).
White Knight ranks and requirements:
1. Novice - 0 kills
2. Peon - 100 kills
3. Page - 200 kills
4. Noble - 400 kills
5. Adept - 800 kills
6. Master - 1600 kills