Yes a skullcap, called a zucchetto in Roman Catholic tradition, is worn by Roman Catholic clergy in some cases. It arose during the time when a tonsure was worn by all clergy as a way to keep the head warm. As a rule, a purple zucchetto is worn by Arch/Bishops, red by Cardinals, and white by the Pope; brown or black zucchetto's are sometimes worn by Franciscan, Benedictine, and Trappist monks.

abides by the vowels taken at ordination

No. Some clergy are cross-functional within very closely related religious sects, but primarily you can only officiate in a religion if you are certified/ordained/appointed by that particular religion.

Part of the power of the Catholic clergy came from their authority to hear confessions and forgive sins. Martin Luther, a monk teaching at the University of Wittenberg in Saxony, said that he "hated this God who punished sinners", and turned to the Bible which he re-interpreted to say that man's salvation was not by acts of penance and repentance, but by faith alone. He argued that all Christians are priests and attacked the withholding of the Sacrament from the laity.

Protestantism began with limits on the power of its clergy, and the Roman Catholic Church had, to some extent, to follow suit.

New light

Cardinal Gaudencio Rosales and Cardinal Vidal

The purpose of the clergy is to preach to gospel of Jesus Christ. To help those whom they have charge of, to comfort the sick and the downhearted. To be readily available when and where ever they are needed. To perform marriages and to conduct services for the dead. He or she is the spiritual leader of a certain area over which they preside.

A black cassock with scarlet piping is a street cassock for a Cardinal, while his choir cassock (the one he wears for Mass and services) is scarlet colored.

Sure a bishop can marry. See for yourself at 1 Timothy 3:2. However, he should be a husband of one wife.

In the Roman Catholic Church Bishops are taken from the priests and conscecrated. The current ruling in the Catholic Church is that Bishops may not be married. There have been at different times in the Church men ordained to the priesthood who have been married - currently we have ordained priests from the Episcopal church who are married. But in the Latin rite and in other rites, such as the Maronites, these married priests are never considering for the bishopric. All men when ordained to any major order in the church take a vow of celibacy which means that if ordained as a deacon and their wife dies, they may not remarry. So, there may be married priests or deacons, but not bishops; and no ordained clergy could ever get married.

As the first contributer above pointed out, there were married Bishops in the first century, but Bishops could not get married

If you think of the system in three levels. The first level is the Church, the second is the nobility, and the final level is the peasant. The Church ruled the society and taught that man was born in sin and the only way to save their souls was to go through the church. They were the middle man between man and God.

The "regular clergy" are also known as "just regulars" and refers to Roman Catholic clerics who live their lives under a specific rule. The term clashes with the term "secular clergy."

Charlemagne

Yes, they can get married. My father was a United Methodist minister!

clergies have different religions

Cardinals wear things that are scarlet, including a cassock, mozzetta, biretta and zucchetto. They also sometimes wear red socks.

Of all the clergy, bishops and abbots were most involved in political matters.

The word clergy itself denotes a group. It refers to the entire body of folks who hold a religious title.

a cassock is a gown worn by priests, deacons and often by the choir during church services.

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