Comedians pretending to be priests and/or lampooning Catholic priests was not a new phenomenon. Between Father Guido Sarducci and Dermot Morgan's earlier standup as "Father Trendy", Rowan Atkinson's turn as an angry rural C of E vicar who has been chosen to be on Songs of Praise, to the savagely cutting "Religion Olympics" by Paul Hogan, the notion that there's humor to be found in the vocation of a pastor or cleric of some sort is a territory that has been and will continue to be mined for comedic effect. Comedy, in essence, is the evolutionary stress valve that prevents human beings from being wounded by things that are depressing or absurd, and what could be more stressful than the whole notion of why we are here, and how angry is God going to be with us, anyway?
Comedy also serves another purpose, historically, and that is to give license to talk about uncomfortable truths. The court jester was the one who could make risky or satirical comments that would bring certain matters to the attention of those in power without risking torture and/or imprisonment for offending the powers that be. The likes of a Stephen Colbert or a Jon Stewart are in a long, LONG list of those who have used the power of laughter to dig into some old, unhealed wounds and try to bring closure to certain matters. Given that Ireland and the Catholic Church were joined pretty much at the hip in some ways, religion was political, and politics influenced by religion. In the 1990s a victim of the Magdalene laundry horrors, Sinead O'Connor, tore up a photo of the Pope on Saturday Night Live (a move that Joe Pesci didn't understand, and responded to in a rather tone-deaf manner) but became a member of a splinter Catholic movement and was in fact ordained in it. That's the historical backdrop of a show that took such a risk it suited up three generations of top notch comedians to do the job.
It is very, VERY dodgy to see Father Ted as "just a show".
Father Jack we know little of anymore, because he has been ruined by substance abuse to the point of near-complete incoherence. Flashabcks show him as being fiery, prone to corporal punishment and with highly conservative views - clearly one who may have joined the Church to stand for old world, old guard values. And yet, the toll of decades of this have reduced him to a shell of a man fuelled only by violence and drink. Lest we write this off as an "irish joke" about alcohol writ large, it's important to note that substance abuse is a real problem with clergy, especially celibate clergy. You're a hired hand for happy events, like weddings and the baptism of children, but a central part of the dark side of things. Funerals. Betrayals. Confessions. Many people run to clergy when they're needed, but then shun them once their needs are taken care of - and unlike a counsellor or doctor who's seen as having a day job but also a separate life, the collar never really comes off. A lone priest in a remote area is often separated from the rest of society with nobody else to turn to. Except, in this instance, two younger men in the same vocation, tending to his personal needs and giving him the company he lacked for so long. In addition to being a commentary on "spare the rod", violent and nasty human beings in clerical robes, it's also very much an attempt to find humor in some very real-world fates.
Father Ted we know best of all. He does appear to have faith, and for all intents and purposes is a competent priest. And yet, having reached middle age, he's not sure if he's done with his life what he's meant to. He longs for glamor and clearly has an addiction to gambling and the high life in Las Vegas. and at one point plans to leave the church to pursue a relationship (albeit with a woman who joins the church, instead). Ironically, though he's on Craggy Island as punishment for embezzlement ("That money was just sitting in my account....") the ones who've meted this out are throwing stones in glass houses. Bishop Brennan (modelled on a real-life bishop in Ireland) has an out-of-wedlock son in America, and has clealy used church funds in pursuit of and to cover up this relationship. Every time we see The Vatican, it's literally a giant party, complete with techno music and revelry. All human beings have doubts. Doubts about their life's work (now we're seeing quarter life crisis as well as midlife crisis but it's an order of magnitude worse when your doubt and lack of faith pertains to... well, faith.
Father Dougal is in the job simply because nobody could think of anywhere else to put him. Childlike both in intellect and personality, he's not at all competent as a priest, and not allowed to perform weddings. When called on to give the Last Rites he chivalrously suggests a nun in attendance do it out of politeness, until he realizes that as a priest he cannot hand off these duties to a woman. He has no real faith and in fact ends up talking a bishop into leaving the church, thinking that everything he learned about in seminary wasn't supposed to be taken seriously and was "a bit of a laugh". In fact, Dougal suggests that Catholic families pressure their first born to succeed in life, and dutifully hand over some middle child to the Church. He'd like to believe in some sort of afterlife, and when drunk cheers out "we're all going to Heaven, wheyyyyyyyyyyy" but you get the feeling that since few people really want the job, there's a lot of people they take in out of necessity that have no business in the field.
Beyond the individuals, the show itself riffs on the need for and/or the point of religion in the 20th century. When Dougal is at risk of being killed in a milk float explosion, the only thing the clergy can think to do is hold a mass. When called a fascist, Ted angrily retorts that he is in NO way a fascist, fascists walk around wearing black ordering people around, whereas priests..... er, would you like a cup of tea? The other side of the coin isn't spared, with a clear expy of Sinead O'Connor angrily harassing the priests whilst wearing boxing gloves that say "Cl*t Power" (the censorship is mine, not theirs). After decades of sectarian violence and the body blows of various scandals, Ireland really needed a good laugh at their social problems, all of them. Some appreciated the humor, many did not. When Dermot Morgan died of a massive heart attack just after the conclusion of their last season, it was seen by some as divine retribution for daring to scoff at the Almighty: for it doth indeed say in The Good Book that "God is not mocked".
It's one of the main reasons why Father Ted has had such longevity, even with its short run. It lends itself to multiple viewings and different levels of humor, from sight gags to missed communication, slapstick to satire. But it may very well be remembered, very long term, for the cutting social commentary that it was.