The foot doesn’t seem like something that would have any spiritual symbology associated with it, but it does. Perhaps because the foot is at the bottom of the body and touches the ground when you are standing, it is associated with the more Earthly or materialistic parts of life. It can also represent the lowest part, the first steps towards spiritual development and enlightenment. When Job writes about the foot that might crush the eggs left on the ground by the ostrich (JOB 39:13-15) , he is talking about the ignorance, the limited understanding of the material brain and mind, which can crush the desire to advance spiritually.
Feet also represent any activities of the body or mind on the physical level but, especially feet that are moving forward, represent completing low-level tasks that are necessary before one can move on to higher, more spiritual work. The Foot of Hera was a symbol of the lowest level of wisdom or the lower mind. The Footprints of Buddha, or just Footprints, represent a path to perfection, enlightenment. It is said that Buddha left a print of his foot in a stone near Kusinara which are a reminder of his presence on earth.
The washing of feet by Jesus and others is therefore symbolic of helping one to move beyond his material aspect and into more spiritual endeavors. Others interpret this as symbolic of humility or brotherhood and, while that may be true, the significant spiritual symbology is preparing one for spiritual advancement.
In Hinduism, feet are symbolic of the lowest aspects of man as they are at the bottom of the body. For this reason, it is very bad manners to point your feet at someone when you are sitting together. It is also considered improper to touch books, pens, musical instruments, or other items associated with the feet as that would be an insult to the god of learning. Yet, Hindus remove their shoes in a temple. That is in essence, symbolically removing their feet, their lower aspect, while in a sacred place.