Was the term “The Way” officially used as a synonym for Christianity during the ages?
It seems that the term the way was not employed officially as a synonym for Christianity during the ages, although it has been used periodically in the history of the Church, either within the Catholic Church or churches of other Christian denominations.
As Anne points out, the phrase was used by the Apostle St. Paul in the Book of Acts:
And asked of him letters to Damascus, to the synagogues: that if he found any men and women of this way, he might bring them bound to Jerusalem. - Acts 9:2
Within the Catholic Church, the phrase The Way is traditionally employed to refer to the Camino de Santiago or as we say in English the Way of the Apostle St.James.
The Way of St. James was one of the most important Christian pilgrimages during the later Middle Ages, and a pilgrimage route on which a plenary indulgence could be earned; other major pilgrimage routes include the Via Francigena to Rome and the pilgrimage to Jerusalem.
Legend holds that St James's remains were carried by boat from Jerusalem to northern Spain, where he was buried in what is now the city of Santiago de Compostela.
Pilgrims on the Way can take one of dozens of pilgrimage routes to Santiago de Compostela. Traditionally, as with most pilgrimages, the Way of Saint James begins at one's home and ends at the pilgrimage site. However, a few of the routes are considered main ones. During the Middle Ages, the route was highly travelled. However, the Black Death, the Protestant Reformation, and political unrest in 16th century Europe led to its decline. By the 1980s, only a few hundred pilgrims per year registered in the pilgrim's office in Santiago.
Whenever St. James's Day (25 July) falls on a Sunday, the cathedral declares a Holy or Jubilee Year. Depending on leap years, Holy Years occur in 5-, 6-, and 11-year intervals. The most recent were 1993, 1999, 2004, 2010 and 2021. The next will be 2027, and 2032.
There also exists a non-denominational ministry known as The Way International which was founded 8n 1942 in Knoxville, Tennessee.
The Way International is a global, non-denominational Christian ministry based in New Knoxville, Ohio. The followers congregate primarily in home fellowships located throughout the United States, two US territories and in over 30 countries. It was founded by Victor Paul Wierwille in 1942 as a radio program, subsequently becoming The Chimes Hour Youth Caravan in 1947, and The Way, Inc., in 1955.
The ministry distributes publications such as The Way Magazine through its company, American Christian Press, and has developed and promotes classes and other programs, some of which are in several languages. It formed The Way Corps, a leadership training program, in 1970.
The Way offers classes in biblical studies to its followers, prominently The Way of Abundance and Power class series. The Way International has given focused attention on first-century Christianity and extensive research into the Church Epistles. It has been described as combining biblical literalism, evangelicalism, Calvinism, ultradispensationalism, and Pentecostalism. The teaching of The Way is based on 2 Peter 1:20 that "no prophecy of the scripture is of any private interpretation" (KJV translation) and they believe the Bible interprets itself in a variety of ways, which is taught in its studies, classes, and publications. TWI teaches that every follower can have an accurate understanding of God's original intent in His Word.
On October 3, 1982, L. Craig Martindale became the second president of The Way. He was followed by Rosalie F. Rivenbark in April 2000. In March 2017, Jean-Yves DeLisle was installed as the fourth president. On March 10, 2020, Vernon W. Edwards was installed as the fifth president of The Way.