The Knights of the Temple Lands were the prelates ruling the Temple Lands.

Technically, the Knights were secular rulers who simply happened to also hold high offices in the Church of God Awaiting. Under Church law, what they did as the Knights of the Temple Lands was completely separate from any official action of the Temple. This legal fiction was of considerable value to them on more than one occasion. (OAR)

All members of the Group of Four were Knights of the Temple Lands. (BSRA)