Today is Ash Wednesday for those churches that follow the Catholic Latin Rite's liturgical calendar, which includes a fair number of Protestant churches.
Ash Wednesday is the beginning of Lent for Western Christians, Lent being the (approximately) forty day long penitential season preceding Easter. Great Lent, the Eastern Christian seasons, precedes Ash Wednesday and commences on Clean Monday for Eastern Christians on the new calendar, but not on the old calendar which has, of course, which departs from the calendar we're otherwise familiar with. The day is named for the Catholic practice, which is observed by at least some Anglicans and Lutherans as well, of placing ashes on the foreheads of those who come to the Ash Wednesday service, with the reminder being made that from ashes you were made, and from ashes you will return.*
For Latin Rite Catholics, Ash Wednesday is a day of fast and abstinence. I.e, they eat only one full meal on this day and it can't include meat, which under Latin Rite Catholic rules does not include fish. For Eastern Christians a much stricter Lenten fast and abstinence set of rules applies. This sacrifice serves the purpose of being penitential in nature.
It also serves to really set Catholics apart, as fasting and abstinence are the rage in the west now, but for purely secular purposes, not all of which square with science or good dietary practices.
For the members of the Apostolic faiths, Lent also serves as a time in which for penitential reasons they usually "give up" something. A lot of people have a really superficial understanding of this, assuming that Catholic "give up" desert or chocolate or something, and in fact quite a few people do something like that. Indeed, as an adult I've been surprised by how many Catholics (usually men) give up drinking alcohol, which means that frequent consumption of alcohol is pretty common society wide in a way that we probably underestimate.
Indeed, just recently, on that, I was asked by an exuberant Catholic Midwestern expat, who seemingly has no boundaries at all, on what I was "giving up" for Lent. This was the week prior to Ash Wednesday at which time I wasn't particularly focused on it myself. The same fellow asked at least one Protestant what she was giving up, with that Protestant being a member of one of the American millennialism religions, to receive a totally baffled reply. Indeed, I'm sure they don't celebrate Lent at all, so the question was odd. Anyhow, he was giving up alcohol and asked if I'd like to join him, to which I absent mindedly said sure. Later he was wondering if I thought it would be tough, which I'm sure it won't be at all and I'll have to find something else to mark Lent really. But that sort of "giving up" line of thinking is very common.
In a lot of Catholic cultures the Lenten penitential observations have traditionally been much stronger, which helps explain
Mardi Gras as we just discussed. Even well after the Latin Rite rules were very much relaxed, in many Catholic areas, including Catholic areas of the United States, people engaged in much more extensive penitential observations with the "giving up chocolate" type thing really sort of an introduction to the practice. In Louisiana, without going into it too deeply, there was traditionally a big spike in births nine to ten months after Easter, which reflected a very widespread serious observation among Catholic couples as to their penitential practice, for example.
Some of that is really coming back, which reflects an interesting trend towards a deeper understanding of their faiths by members of the Apostolic faiths and even a return of Lenten traditions in some Protestant ones. During the full "Spirit of Vatican Two" era there was a lot of attention devoted to not giving anything up but rather to work on some spiritual need. I.e, be self reflective and work on what that lead you to. At the same time, the misuse of the word "fasting" became very common, with there being advice, even from the clergy, to fast from things other than food or drink. You can't really fast from sinful behavior, or from narcissism, for example. You can't even "fast" from the Internet, although "giving it up" for Lent might be a darned good idea (one that I really ought to consider, probably).
A lot of that is now passing and there's been a real return to more traditional observations of Lent, including fasting but also forms of dedicated worship and observation.
Which brings me to the next thing about "giving up". One feature of this season is that many Apostolic Christians, as it is the season of repentance, have used the season to break bad conduct when there's support, spiritual and temporal, for doing it. People with alcohol problems will use it to break them, smokers will quit smoking during Lent so they can quit smoking. And sometimes people with serious attachments to sin take it head on during Lent, with some people I've known even announcing the renouncement of what are very serious sins from a Christian purpose over Lent in the hopes of breaking from the permanently. And many who do that, succeed at doing that.
Which in turn takes us to our final observation. This season, which is lead by the Apostolic faiths but which is observed by at least some of the Protestants as well, tend to turn the self indulgent retained Puritan abstinence on its head. I've noted this before, but North American and the Northern Europe may have strayed enormously from Calvinist influence in terms of faith, but not in terms of the concept that public suffering is really necessary. That retained concept explains in large part the real focus in these lands, as opposed to others, in "giving up" something for no real purpose other than the sense it must be done. People give up all sorts of things that Apostolic Christians around the world give up for forty some days, and often on a declared permanent basis (they fail at it more often than not), with it being notable that the purely secular nature of that makes it shallow from the onset. Indeed, plenty of people who will spend Lent scoffing at Catholics for Lent will spend part of the season or all of it on some no carb, or no meat, or whatever, diet, for no real reason other than a constructed one. Suffering, in many instances, is the ultimate goal of those efforts, but suffering without something to redeem it.
For Apostolic Christians, all fasts are followed by feasts, and that's something to remember.
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*I don't think this is a practice in the East and its not a requirement for Catholics, something that in fact even confuses some Catholics. Ash Wednesday is widely observed by Catholics and the placing of the ashes isn't restricted to Catholics. Perhaps for that reason quite a few Catholics assume it is a Holy Day of Obligation.
One thing of note here is that Ash Wednesday also serves to point out to everyone who is a Catholic, as if a person has ashes on their head, they're probably Catholic, although not necessarily. By the same token, if you are known to be a Catholic and don't make it to Ash Wednesday you'll tend to get comments about it.