When Forever 21 opens its doors in Dublin's Jervis Shopping Centre next month, both shoppers and job-seekers will be thrilled to find a flood of designer styles for knockdown prices and a swathe of new jobs.

However, not all customers will be quite as happy about the outlet's chequered past or the religious undercurrents in the store, which is the company's first venture into Europe.

Sure to strike the first chord is the biblical inscription "John 3:16" hidden away at the bottom of the shopping bags, a passage which states "For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him shall not perish, but have everlasting life."

The inscription has sparked fury among shoppers in America, but has been kept as a feature by founders, husband and wife team Don and Jin Sook Chang.

Both are devout Christians who attend 5:30am prayer services and have given millions to their church.

Some US customers said they brought their own bags into the store, accusing the Changs of discreetly using them to spread their own religious messages. The family has also been accused of hypocrisy after a string of controversies.

The fashion firm has been the subject of over 50 copyright infringement proceedings, and has been sued by top fashion designers such as Anna Sui, Gwen Stefani and Diane Von Furstenberg.

When Anthropologie, better known as being part of the Urban Outfitters brand, said Forever 21 copied nine of its copyrighted garments, Don and Jin Chang issued a statement saying: "In the course of every business like ours, these suits are resolved," before quoting the proverb: "Where no oxen are, the crib is clean."

Most notably though, the store was the subject of a long-running dispute after 19 employees claimed to be working in factories infested with cockroaches, and said they were being paid less than the minimum wage and did not get overtime.

The workers also said they were required to work between nine and 13 hours a day without being allowed meal or rest breaks.

The case eventually reached a settlement after years of proceedings and countless boycotts across America in support of the workers.

Most recently, Forever 21 came under fire for launching a maternity line which appeared to be geared towards teens and women in their early 20s.

Last August, Fox News carried a report that three of the five states in America where Forever 21 sold the clothes currently have high rates of teenage pregnancy.

Forever 21 denied all allegations, with executive vice president Larry Meyer saying: "Any relationship between teen pregnancy rates and the locations of our stores is unintentional."

Oblivious to the storm consistently brewing around their company, the founders are known to keep a low-profile, quietly amassing an estimated $2bn fortune from their 460 worldwide stores while also attempting to spread the word of their church under the radar.

One employee, Rowena Rodriguez, who is a fashion consultant, said she was born again with Jin Chang's help. "In the short time I worked with Mrs Chang, my life was transformed, and I accepted Jesus Christ as my Lord and Saviour."

Rodriguez also said she was constantly asked why Forever 21 prospered against the odds. "I usually say, if you really want to know, I'll tell you. But you won't believe me... The Changs love Jesus."

Founder Don Chang's own rise from rags to riches, – he is now on the Forbes rich list – has been well-documented.

Chang originally did three jobs at once – working in a coffee shop, doing janitorial work and pumping gas. He has said that while he was at the gas station, he was hit by the inspiration to enter the fashion industry, after noticing that the merchants had the best cars. In 1984, the couple opened a clothing store in Los Angeles.

Filling the store with small tops, miniskirts and swathes of cheap jewellery ensured that profits rocketed in the store from $35,000 to $700,000 in that first year alone.

That store was a paltry 900sq ft, paling in comparison to Jervis's 70,000sq ft store, which is the latest chapter in the tale of a massive expansion.