Why and when did the clergy go from the black robe to the white robe and stoles? Years ago the pastor wore black, as it was a sign of humility. What is the thought process of this change?
Christian Worship: Manual, the companion book to Christian Worship: A Lutheran Hymnal, has a helpful section of information (pages 95-104) that addresses your question. Here are some excerpts:
“During the first four centuries after Christ, pastors did not have the custom of wearing special clothes for worship…The alb became the customary worship vestment only as public worship became more formal and ceremonial, sometime around the fifth century.
“…The garment the medieval pastor would have worn when he came to church was the street attire of his own era, the cassock…Since the clergy were also the teachers at the schools and universities, the cassock was what teachers and professors wore when they taught. One might compare the cassock to our modern sport jacket and slacks, or to a pinstripe suit…Only under the influence of the Reformed (who rejected almost all of the church’s historic worship legacy) did the ‘Geneva’ or academic robe come to replace the alb as the worship vestment.
“…Those who rejected the historic worship vestments, first in Germany and later in America, were aligned more often with the Calvinists, Pietists, and Rationalists than they were with the orthodox Lutherans…The Rationalists were decidedly anti-authoritarian…Their clergy dressed in the black academic robe not because it was a worship vestment, but because it was not a worship vestment. Like many Protestants today, they wore the everyday professional garb of the medieval scholar and the modern magistrate, the Geneva gown.”
When it comes to the color of the pastors’ vestments, Christian Worship: Manual, explains the significance of liturgical colors. “White: color of the godhead and eternity; color of the robe of the glorified Christ and of the angels and saints in heaven; color of perfection, joy, purity.” “Black: the absence of color; symbolic of death.”
“The stole is traditionally reserved for those who hold the office of the pastoral ministry.”
In all of this, we want to keep Christian freedom in mind. God has neither commanded nor prohibited the use of vestments like these.