“Lost” (8 p.m., ABC) returns next week for its final season, and ABC helps viewers prepare with a repeat airing of last season’s epic two-hour finale.

While watching this absorbing head-scratcher last May, I couldn’t help but note how the show’s sci-fi storylines and soap-opera plots were giving way to overt religious allegory. ABC has only confirmed my suspicions with its recent promotions for the final season.

TV commercials feature a Willie Nelson version of “Amazing Grace.” And just last week, ABC’s publicity department re-leased a photo of the cast sitting at a table resembling the figures in Da Vinci’s The Last Supper. Or was it The “Lost” Supper?

Some may argue that I’m reaching here. But hints of religious symbolism on “Lost” are as hard to ignore as they are difficult to fathom.

Locke returns as both a resurrected figure and as a leader/rebel of sorts who plans to kill and overthrow the God-like Jacob.

To complicate matters further, Locke is both a risen “savior” and a man who died by hanging, like Judas. So who is he?

A complete enigma, the Jacob figure not only sports an Old Testament name but is surrounded by hieroglyphs and other signs of ancient beliefs.

Speaking of names, how about Jack’s last name, Shepherd? Or the name of his dead (?) father — Christian Shepherd?

Broadcasters and advertisers in search of large audiences have long avoided programs with dogmatic religious content, considering them divisive and controversial. Recent statements by Brit Hume and Pat Robertson have only confirmed those suspicions.

But religion is so woven into our lives that to ignore it entirely leaves an arid spiritual and cultural void. Bravo to shows like “Lost,” brave and smart enough to wade into these waters and to do so with a sense of mystery and wonder.

Tonight’s other highlights

• A repeat “Nova” (7 p.m., PBS, check local listings) looks at monarch butterflies.

• Avril Lavigne and Katy Perry guest judge on “American Idol” (7 p.m., Fox).

• Ted’s brother needs help on “Better Off Ted” (7:30 p.m., ABC).

• An agent becomes a target on “NCIS: Los Angeles” (8 p.m., CBS).

• “Frontline” (8 p.m., PBS, check local listings) exposes credit card risks.

• Alicia finds herself attracted to a fellow lawyer on “The Good Wife” (9 p.m., CBS).