Shocking as it may seem to newer viewers of British TV, there used to be a BBC-ITV ratings battle between shows in which viewers sang hymns and told Bible stories.

The Sunday stand-off between the public service Songs of Praise and the commercial Highway was the biggest manifestation of what broadcasters called the “God slots”. Broadcasting guidelines required both main networks to screen not only sacred song anthologies, but also live church services, and late-night “religious and ethical” discussion shows. The emphasis was almost always on respecting Britain’s residual state religion, Christianity.

Increased competition for viewers caused by channel expansion led networks to pray successfully for release from days of holy obligation: Songs of Praise, though relegated to a BBC1 Sunday lunch-time slot, is the last relic of the old-time religion in the schedules, except for specials to mark Christmas, Easter and, now, Jewish, Muslim, and Sikh festivals.

But, though the God slots have gone, religion seems to be achieving a televisual second coming. Two series about American Christian evangelical families have launched coincidentally in the UK this week: HBO’s The Righteous Gemstones (Sky Comedy) and MGM’s Perpetual Grace, Ltd (StarzPlay). On Netflix, Messiah, in which a Christ-like bearded preacher figure appears in the contemporary Middle East, proved a recent hit.

Jesus walks? ... Messiah on Netflix. Photograph: Hiba Judeh/Netflix

Next month, when the 2020 Bafta TV award nominations are announced, there seems sure to be mass recognition of the second season of Fleabag, an agonised “love story” between Phoebe Waller-Bridge’s libidinous singleton and Andrew Scott’s “hot priest”. Netflix’s The Young Pope, which won Jude Law an Emmy nomination as a pontiff as likely to be seen in Speedos as white robes and papal tiara, has just been followed by a sequel, The New Pope.

The fear of faith-leaders and believers, though, is that this new religious broadcasting sees the obligatory reverence of earlier TV decades replaced by ritual ridicule.

The Righteous Gemstones and Perpetual Grace, Ltd are dark comedies that present American evangelical churches as cynical and hypocritical exercises in fleecing the vulnerable out of money while their pastors live like rock stars. John Goodman’s Pastor Eli Gemstone has a fleet of three private jets, named The Father, The Son and the Holy Spirit. Played by Ben Kingsley, who has curiously chosen to channel the accent of Anthony Hopkins, Pastor Byron Brown, CEO of Perpetual Grace, Ltd, says, when finances are mentioned: “We do alright –our church,” but we know to take this as severe understatement.

This suggestion of American evangelism as fraudulent cant and deception descends from Sinclair Lewis’s influential 1927 novel Elmer Gantry, in which a con-man joins a revivalist preacher; it was filmed in 1960, with Burt Lancaster as the fraud for the Lord.

A newer influence on the two new American TV variations on this narrative, though, is the present US president. Although Donald Trump has been married three times, and his frequent claims of not having time to read books were assumed to include the Bible, the Christian fundamentalist vote was key to his election, and, as he seeks a second term, he has been filmed praying with believers. So The Righteous Gemstones and Perpetual Grace, Ltd - in exploring the uses and mis-uses of piety - can be seen as part of liberal Hollywood’s response to the shock of the 2016 election.

Indeed, while the Bible shows Christ telling secular stories – about wise and unwise virgins, or the best way to serve wine at a wedding – to make religious points, this wave of TV dramas are often parables that use religion for secular purposes.

Both The Young Pope and The New Pope, Messiah and Riders of the Storm (a Danish church drama by Borgen creator, Adam Price, seen here on Channel 4) all use ecclesiastical power struggles as a proxy for contemporary politics. Each employs thriller tropes, such as conspiracy and espionage: in Messiah, the CIA and Mossad investigate who the rumoured second Jesus really is.

Less generically, The Young Pope, The New Pope and Riders of the Storm offer frequent parallels with parties and parliaments. This is tempting because the tensions in church leaderships between orthodoxy and reform, purity and pragmatism, are exactly those that play out in the Commons, Congress, and other legislatures.

Although Roman Catholic cardinals are asked to “listen to the Holy Spirit” while choosing the next occupant of the throne of St Peter, director Paolo Sorrentino’s sumptuous big-budget reconstructions make clear that the process is as prone as any other electoral process factions, tactics, and mistakes.

By having John Malkovich’s John Paul III serve while Jude Law’s Pius XIII lies in a coma, The New Pope contrives an ideological fight between supporters of two living pontiffs, a strand that would once have seemed absurd but is being played out in the real Vatican as the retired Benedict XVI shadows his successor Pope Francis. (A situation explicitly dramatised in Netflix’s multi-Oscar-nominated film, The Two Popes).

Serving God and Mammon ... The Righteous Gemstones. Photograph: HBO

Yet Sorrentino’s series, while properly referencing the paedophile and financial scandals that have damaged Catholicism, are not satirical about faith or religion. Law’s Pius XIII is essentially a good man who may justify another character’s description as “the only pure soul who ever set foot” in the Vatican. In these shows, a Pope is seen as dangerous if he turns the work of the church towards God or human justice rather than priestly power.

In the Bible, Christ frequently warns that it is not possible to serve both God and Mammon. Though differing in tone and approach, The Righteous Gemstones, Perpetual Grace, Ltd, and both The Young Popeand The New Pope all critique the contemporary Christian churches for using God as a means to make money. Rightwing and evangelical believers may dismiss this as a leftwing economic agenda, but the message is Biblically respectful.

Even Sorrentino’s tendency to risk giving Jude Law a chill – he is seen wearing only swimming trunks in the first season, his genitals covered by a skimpy hospital towel in the second - might charitably be seen as an acknowledgment that Christ died not in a neck-to-foot cassock but nearly naked in a loincloth.

And, although the second run of Fleabag features a Catholic priest breaking his vow of celibacy, the show never doubts the faith of the Andrew Scott character. What is remarkable about the sex scene is that it is retrospectively revealed to have been the priest testing whether sex could ever bring him the rewards that his love of God does. It is a measure of the complexity of Waller-Bridge’s writing that an act that is, in the terms of the character’s professional contract, a sin, becomes an unexpectedly reverent affirmation of his beliefs.

The God slot may have been gone, but it seems the new slots religion is finding on TV can be a more intelligent and interesting exploration of faith and theology than the late Roy Castle or Sir Harry Secombe singing hymns in a cardigan on a Sunday afternoon.