The Catholic church has two-thousand years of history behind it. In that time we’ve developed a highly specialized language. Like all jargon it can be confusing — for those on the inside and the outside alike. (Spend ten minutes with your local IT or medical professional and you’ll know what I mean.)
Even simple things, like the designation of certain roles in the church, can be perplexing. Do you know the difference between a nun and a sister? What is a monk? Are all monks priests? Are all priests monks? What about Deacons?
In the spirit of simplification, let me share a way to think about the different roles of religious life in the church.
Broadly speaking, religious vocations in the Catholic church can be categorized as “contemplative” or “active”. Those who are called to a contemplative life live apart from society in a monastery or cloister. A recent Aleteia article explains it this way:
This usually involves living and working within a designated “enclosed” space, off-limits to all but priests, medical personnel and workmen, and leaving the enclosure only for medical issues or business involving the monastery. As with monks, a nun’s “work,” aside from what helps to materially support the house, is prayer, which is ongoing throughout the day and offered for the sake of the Church and the world.
In some cases, the cloister restrictions are not as strictly enforced. Some orders of nuns, while technically cloistered, conduct works of charity or education, interacting with the public. For example, the Visitation Sisters are technically cloistered nuns but teach school.
On the other hand, those with an active vocation are called to live in the world and provide direct service. Perhaps the most famous of these would be Mother Teres’a Missionaries of Charity.
As a general rule, if you see a woman wearing a habit or some other distinctive mark of religious life, you’re probably seeing a “sister”. The term “nun” is more often reserved for those living the contemplative life.
Similar rules hold true for monks, priests and friars with a couple of additional complications. Priests can be attached to the local diocese — these are called “secular” or “diocesan” priests. Or, they can be attached to a particular community or order — think “Franciscan”, “Jesuit”, or “Paulist”. Or they can be monastic — think “Benedictine”.
Aleteia summed it up this way:
Diocesan priests do not take vows of poverty and may possess and inherit property.
Priests vowed to a religious order (like the Franciscans, Dominicans, etc) or a monastic community (like the Benedictines or Cistercians) do make vows of poverty, surrendering any income they generate through their works to their superiors. So a Dominican writer earning profits from his books will turn those royalty checks over to the Order of Preachers. A Trappist writer will turn his earnings over to his abbot or prior, for the benefit of the whole community.
In an order or a monastery, some of the men may be ordained as priests which allows them to perform the sacraments, while others are brothers who have taken vows. The Aleteia article goes more into depth of the various shadings of meaning.
If you meet someone in religious life and are curious about the details of their particular calling, the best and simplest way to learn more is to ask them. The overwhelming majority of religious I’ve met are more than happy to tell you all about their vocation.
— Dad of Evan