The Knight of Disks (remember that Knights in the Thoth deck are equivalent to Kings in other decks) represents the slow, inevitable energy of an Oak Tree’s growth.
He is “fire of earth” in the Thoth system. Think of the incredible dense power contained in molten lava.
Rather than charging into the fray, this Knight appears to be surveying the land to decide where to plant his crops. The horse, also, appears to be more concerned with the grass about their feet than with anything on the horizon.
Steady and reliable, this Knight may also seem a bit dull and dense. He appears as a reminder to take care of our basic physical and material needs first, as a basis for all of our other activities and explorations.