Notice in the Gospel how Jesus begins His discourse by stating the proper perspective on the authority of the scribes and Pharisees who “have taken their seat on the chair of Moses.” Yes, that chair was the seat of authority in the same way the chair of the Bishop—cathedra, in Latin, from which we derive the word, cathedral—is the seat of authority as designated by Christ when He gave the apostles, particularly St. Peter, the authority to govern His Church. The phrase, chair of Moses, however, contains an important qualification that requires an in-depth knowledge of the book of Exodus. The Jews of Jesus’ day, especially the Scribes, Sadducees and Pharisees, would have had this experiential knowledge from a constant reading of the Law, the first five books of scripture.
From his first encounter with God at the burning bush, Moses experienced problems with the stubbornness of God’s “chosen people.” He often resented God calling him to lead “your people” out of Egypt and to the promised land. He did not take personal ownership of these people until His encounter with God at Mt. Sinai, where his attitude changed.
We know the story of the their impatience with Moses, and God, during his 40 days of fasting and prayer on Sinai. Taking their loss of Hope to Aaron, they begged him to “make us a god who will be our leader” (Ex. 32:1). Moses did not know what was happening but God knew. He threatened to destroy these people and start over with Moses, promising “to make of you a great nation” (Ex. 32:10). Moses rejected God’s offer to become a great nation whose descendants would inherit all God promised to the “stiff-necked” people below. Instead, he pleaded their cause before God who relented in His threatened punishment. From that point on, Moses took on a new attitude. He became not only their leader but their guardian before God. Moses took these people as his own.
This was the chair of Moses to which Jesus refers; it is a chair whose authority includes sacrifice—something the Scribes and Pharisees lacked in their authority.
Notice the verbiage at the end of the Gospel. Jesus says, “Whoever exalts/humbles himself will be humbled/exalted.” He uses an active verb to denote what we do for ourselves and finishes with a passive verb to denote what will happen to us, by the hand of God. Thy Will be done.