The rite of discalceation, or uncovering the feet on approaching holy ground, is derived from the Latin word discalceare, to pluck off one’s shoes. The usage has the prestige of antiquity and universality in its favor.
That it not only very generally prevailed, but that its symbolic signification was well understood in the days of Moses, we learn from that passage of Exodus where the angel of the Lord, at the burning bush, exclaims to the patriarch, “Draw not nigh hither; put off thy shoes from off thy feet, for the place whereon thou standest is holy ground.”  Clarke thinks it is from this command that the Eastern nations have derived the custom of performing all their acts of religious worship with bare feet. But it is much more probable that the ceremony was in use long anterior to the circumstance of the burning bush, and that the Jewish lawgiver at once recognized it as a well-known sign of reverence.
Bishop Patrick entertains this opinion, and thinks that the custom was derived from the ancient patriarchs, and was transmitted by a general tradition to succeeding times.
Abundant evidence might be furnished from ancient authors of the existence of the custom among all nations, both Jewish and Gentile. A few of them, principally collected by Dr. Mede, must be curious and interesting.
The direction of Pythagoras to his disciples was in these words: “[Greek: Anypo/dêtos thy/e kai pro/skynei];” that is, Offer sacrifice and worship with thy shoes off.
Justin Martyr says that those who came to worship in the sanctuaries and temples of the Gentiles were commanded by their priests to put off their shoes.
Drusius, in his Notes on the Book of Joshua, says that among most of the Eastern nations it was a pious duty to tread the pavement of the temple with unshod feet.
Maimonides, the great expounder of the Jewish law, asserts that “it was not lawful for a man to come into the mountain of God’s house with his shoes on his feet, or with his staff, or in his working garments, or with dust on his feet.” 
Rabbi Solomon, commenting on the command in Leviticus xix. 30, “Ye shall reverence my sanctuary,” makes the same remark in relation to this custom. On this subject Dr. Oliver observes, “Now, the act of going with naked feet was always considered a token of humility and reverence; and the priests, in the temple worship, always officiated with feet uncovered, although it was frequently injurious to their health.” 
Mede quotes Zago Zaba, an Ethiopian bishop, who was ambassador from David, King of Abyssinia, to John III., of Portugal, as saying, “We are not permitted to enter the church, except barefooted.” 
The Mohammedans, when about to perform their devotions, always leave their slippers at the door of the mosque. The Druids practiced the same custom whenever they celebrated their sacred rites; and the ancient Peruvians are said always to have left their shoes at the porch when they entered the magnificent temple consecrated to the worship of the sun.
Adam Clarke thinks that the custom of worshipping the Deity barefooted was so general among all nations of antiquity, that he assigns it as one of his thirteen proofs that the whole human race have been derived from one family.
A theory might be advanced as follows: The shoes, or sandals, were worn on ordinary occasions as a protection from the defilement of the ground. To continue to wear them, then, in a consecrated place, would be a tacit insinuation that the ground there was equally polluted and capable of producing defilement. But, as the very character of a holy and consecrated spot precludes the idea of any sort of defilement or impurity, the acknowledgment that such was the case was conveyed, symbolically, by divesting the feet of all that protection from pollution and uncleanness which would be necessary in unconsecrated places.
So, in modern times, we uncover the head to express the sentiment of esteem and respect. Now, in former days, when there was more violence to be apprehended than now, the casque, or helmet, afforded an ample protection from any sudden blow of an unexpected adversary. But we can fear no violence from one whom we esteem and respect; and, therefore, to deprive the head of its accustomed protection is to give an evidence of our unlimited confidence in the person to whom the gesture is made.
The rite of discalceation is, therefore, a symbol of reverence. It signifies, in the language of symbolism, that the spot which is about to be approached in this humble and reverential manner is consecrated to some holy purpose.
Now, as to all that has been said, the intelligent mason will at once see its application to the third degree. Of all the degrees of Masonry, this is by far the most important and sublime. The solemn lessons which it teaches, the sacred scene which it represents, and the impressive ceremonies with which it is conducted, are all calculated to inspire the mind with feelings of awe and reverence. Into the holy of holies of the temple, when the ark of the covenant had been deposited in its appropriate place, and the Shekinah was hovering over it, the high priest alone, and on one day only in the whole year, was permitted, after the most careful purification, to enter with bare feet, and to pronounce, with fearful veneration, the tetragrammaton or omnific word.
And into the Master Mason’s lodge–this holy of holies of the masonic temple, where the solemn truths of death and immortality are inculcated–the aspirant, on entering, should purify his heart from every contamination, and remember, with a due sense of their symbolic application, those words that once broke upon the astonished ears of the old patriarch, “Put off thy shoes from off thy feet, for the place whereon thou standest is holy ground.”